Chess Openings Wizard – Program Versions

Last Report:  February 29, 2024

“Before you read the bug report…”

Chess Openings Wizard is constantly under development to stay current with new engines, best practices, new versions of Windows, Macintosh, iPhone, iPad, and Android, and the ideas from players who use it every day.

That said, it is risky to make the bug list available to the public. The vast majority of software publishers keep their bug list private so as not to discourage new purchases who might assume that the software has too many problems because everything known about the program is in this list.

Rest assured, Chess Openings Wizard is used by more than 66,000 chess players.

I publish our bug list because:

I personally appreciate it when a software maker tells me about any known problems for programs that I want to purchase.

I think chess players are smart enough to realize that all sophisticated software has bugs, and that listing them publicly is my way of making sure you know it’s being worked on.


Mike Leahy, The Database Man!

The most recent builds of Professional and Express contain these changes:

  1. When you purchase a new program, your permanent product key will be emailed immediately.
  2. You can install your product key on up to three of your computers. (Please don’t share your key.)
  3. The registration system does not require a connection to the internet.
  4. You can log in and get the latest download links and your product keys any time.

There are currently no free trial versions of Chess Openings Wizard.

If you are using a version prior to 2016, here are the top ten reasons to upgrade.

Chess Openings Wizard ProgramLatest BuildReleased
Professional WindowsBuild 196February 29, 2024
Professional MacintoshBuild 195February 28, 2024
Express WindowsBuild 191February 2, 2024
Express MacintoshBuild 190February 1, 2024
iPad and iPhoneBuild 65November 5, 2023
AndroidBuild 66November 6, 2023
COW Engine Server for WindowsBuild 8November 12, 2018
COW Engine Server for MacintoshBuild 9November 19, 2018

Changed in build 195 COW Professional for Macintosh and build 196 for Windows

Build 195 replaced build 193 for Macintosh. Build 196 replaced build 192 for Windows.

Stockfish 16.1 was added.

Better shortcut keys were chosen for pasting engine analysis and adding pedigree moves.

Issues with the training wizard rewinding to last branch were fixed.

A bug that removed the title of the ebook when starting Stockfish was fixed.

Changed in build 192 COW Professional for Windows

Build 192 replaced build 188 for Windows. Build 193 replaced build 187 for Macintosh.

Game window allows the board to flip.

Issues with drawing last move arrows are fixed.

Issue with training wizard not requiring multiple correct moves fixed. (Hud D.)

Ctrl+C now copies the current line to the clipboard as PGN for pasting into other apps.

Program Preferences Training tab has more controls for training messages.

Training Wizard “Not in the Book” message now appears closer to where the mouse is for easier clicking.

A number of training wizard message windows can be dismissed by pressing the Enter or Esc keys.

Training Wizard has been overhauled and will no longer be confused if you make more than one incorrect move in the same line.

Training Wizard will optionally show a warning when you reach a position where you made an incorrect move in the past.

Fixed the multimedia cursor issue when recording with Black at the bottom of the diagram.

Changed in build 189 COW Express for Windows and build 190 COW Express for Macintosh

Build 189 replaced build 186 for Windows. Build 190 replaced build 179 for Macintosh.

This build adds the ability to copy the diagram to the clipboard and export the diagram to three different formats (BMP, PNG, JPG).

This build fixes a bug that would keep the final move from being tested in training mode.

The training wizard has been expanded to allow resetting training for only the current line. It can be made to optionally do this whenever a new move is added to an ebook.

The training window has been resized for lower resolution monitors.

Changed in build 187 COW Professional for Macintosh and build 188 for Windows

Build 187 replaced build 184 for Macintosh. Build 188 replaced build 183 for Windows.

This build adds the ability to copy the diagram to the clipboard and export the diagram to three different formats (BMP, PNG, JPG).

Changed in build 186 COW Express for Windows

Build 186 replaced build 175 for Windows.

This build fixes a bug that would keep the final move from being tested in training mode.

The training wizard has been expanded to allow resetting training for only the current line. It can be made to optionally do this whenever a new move is added to an ebook.

Changed in build 183 COW Professional for Windows and build 184 for Macintosh

Build 183 replaced build 181 for Windows.

Build 184 replaced build 182 for Mac.

This build changes blindfold mode in the training wizard so that the piece being dragged is displayed.

This build fixes a bug that would keep the final move from being tested in training mode.

The training wizard has been expanded to allow resetting training for only the current line. It can be made to optionally do this whenever a new move is added to an ebook.

Changed in build 182 COW Professional for Macintosh

Build 182 replaced build 180.

This build adds blindfold mode to the training wizard.

The copying and pasting of engine analysis into the comments was improved by adding a new line to the comments so that grabbing engine analysis a second time creates a new paragraph.

Changed in build 181 COW Professional for Windows

Build 181 replaced build 176.

This build adds blindfold mode to the training wizard.

The copying and pasting of engine analysis into the comments was improved by adding a new line to the comments so that grabbing engine analysis a second time creates a new paragraph.

Changed in build 180 COW Professional for Macintosh

Build 180 replaced build 177.

Added Google Drive support.

Added Stockfish 16.

Changed in build 179 COW Express for Macintosh

Build 179 replaced build 178.

Added support for Google Drive.

Added Stockfish 16.

Changed in build 178 COW Express for Macintosh

Build 178 replaced build 174.

Fixed issues with Mac OS Sonoma and HiPDI 4K displays.

Changed in build 177 COW Professional for Macintosh

Build 177 replaced build 171.

Fixed issues with Mac OS Sonoma and HiPDI 4K displays.

Changed in build 176 COW Professional for Windows

Build 176 replaced build 168.

Added Google Drive support.

Added Stockfish 16.

Updated online help.

Changed in build 175 COW Express for Windows

Fixed 140MB Dropbox limitation.

COW build 175 replaced build 162.

Fixed bug that failed to store diagram arrows.

Changed in build 174 COW Express for Macintosh

COW build 174 replaced build 166.

Uses Stockfish 15.1 and includes separate engines for Intel and Silicon Macs.

Fixed 140MB Dropbox limitation.

Fixed bug that failed to store diagram arrows.

Fixed F8 and Go menu to go back one ply.

Changed in build 168 COW Pro for Windows

COW build 168 replaced build 160.

Uses Stockfish 15.1.

Fixed menu command to go back one ply (also F8 function key).

Fixed 140MB Dropbox limitation.

Changed in build 162, 166

COW Express adds the ability to play back multimedia (made by the Professional version). It also adds diagram marks (dots and X’s on squares and arrows in four colors) accessed by right clicking on the diagram.

COW Express Macintosh uses Stockfish 15.

Changes in build 160, 161

COW adds functions to the Commands menu. You can synchronize the Informant symbols to match the engine analysis. You can mine for novelties by searching for positions where the Informant symbol does not agree with the numeric assessment from the engine.

COW Pro Build 160 for Windows replaces build 157.
Build 161 for Macintosh replaces build 156.

Changes in build 156, 157

COW now runs natively on Macs with M1 Silicon chips. It is fully tested through Monterey 12.1.

COW is well tested on Windows 10 and 11.

Introduces multimedia recording (diagram marks synchronized to recorded audio), arrows for the engine’s best move, and static diagram marks (circles and arrows on the diagram). The arrows can be four different colors. Marking squares includes using an X. The key strokes (Ctrl, Alt, Shift) match those of lichess.

Matching updates for iPhone, iPad, and Android phones and tablets are coming. We’ll start with opening the newer format ebooks and then later add more support for multimedia.

The data format changed from build 137 onward to accommodate multimedia recording. With that, the default folder for ebooks is now “Chess Openings Wizard” in the Documents folder.

Bugs were fixed, including the correct restoration of chosen diagram settings such as custom square colors.

The Windows installer no long installs the sample ebooks which in the past caused confusion when the app was installed by a Windows admin account. The app now installs the sample ebooks.

The Macintosh DMG is now compressed and downloads in one third the time.

Stockfish 14.1 is included with the Windows version and the Macintosh version.

Minor bugs were fixed and many small improvements were made.

Changes in build 136

Replaces build 128 Professional for Macintosh.

Adds the new Foley function which automatically compares your repertoire to the recent games of any lichess player in just a few seconds. Video instruction here

This includes the killer Foley function detailed below.

Changes in build 132

Replaces build 127 Professional for Windows.

Fixes a problem dealing with PGN files containing incorrect sub variations that would cause PGN imports to freeze.

Adds the new Foley function which automatically compares your repertoire to the recent games of any lichess player in just a few seconds. Video instruction here

Allows lichess players to prepare against an online opponent by comparing how they played their last 100 games with your repertoire (as well as view individual games by any lichess player).

Also allows the download of your games in PGN or the games of any player.
This is a killer feature.

Changes in build 126, 127, 128, 129

Replaces build 119 and 123 Express.

Build 128 replaces build 117 Professional for Macintosh.

The last played lichess game of any player can be instantly imported into your chosen repertoire ebook, automatically fast forwarded to the novelty from that game.

The default engine is Stockfish 12 in Windows (still Stockfish 10 on Mac).
The engine analysis appears in figurine notation (like the candidate moves).
The old limitation of 255 characters for file paths has been lifted.
The program now stores its settings in an .INI file.
The training wizard now allows you to set a maximum move number, allowing you to limit through move 9 for example.
The Training Wizard setup window has a new Help button.
Fixed the Go menu’s Jump to Next and Jump to Previous named positions.
The limit of 100 imported plies was lifted to 500 (allowing 250 move games).
You can suppress duplicate comments from imported PGN games.
PGN import adds hyphens to game dates (2020-09-15 rather than 20200915).
Ctrl+Alt+T starts training immediately with the current settings by selecting Commands | Train Now.
Games | Find Games with this Move Order... now automatically fills in the move order with the line in the active ebook.
The app will ask your permission to overwrite an existing file when downloading a matching file from Dropbox.

Changes in build 123

This is an Express build for Mac. It has all the changes since build 107 plus it uses figurine notation in the engine analysis.

It will load the settings from build 107, the last released version.

It is, of course, Catalina friendly.

It fixes a problem with the menu items that load the next and previous board names in endgame and tactics puzzle ebooks.

It will run Stockfish 12. However, that engine could not be included in this update due to Apple security issues with “hardened runtimes.”

Aesthetic changes were made so that certain large numbers had commas, and certain messages would not word wrap.

Changes in build 120

Replaces build 104 for Macintosh. Includes all improvements in builds 115-199.

Changes in build 119

Replaces build 93.

The Games | Select Game… option now correctly goes to the list of searched games.

Candidates moves that match the moves of the loaded game (in the Game window) are marked with a ‘G‘.

Build 119 Express now supports algebraic hints in the diagrams.

When pasting in a PGN game, the game is also loaded into the Game window (as well as adding the moves to the ebook).

Changes in build 115, 116, 117

A shortcut key was added for grabbing (copying and pasting) engine analysis.

A bug was fixed that affected large PGN imports (more than 30,000 games at one time).

A bug was fixed that sometimes hindered loading more than 2,000 named positions.

Changes in build 113

The program now checks to see if there is an update available.

Backsolving fixes a bug when a line is added with a blank Informant rate.

Changes in build 112

Diagram can have algebraic hints in the frame.

Backsolving fixes a bug when the only candidate’s Informant rate symbol is blank and the setting to ignore blank rates is checked.

A check box option to ignore blank rates was added to the program settings (for real time backsolving).

Bug fixed that did not allow the first move of a named position (from tactics or endgame puzzles) to be added to a speed learning set.

Backsolved rate and numeric assessment are instantly updated when program settings are changed (to ignore blank rates for example).

Build 112 looks for the settings from build 92 and uses them if it can, saving the headache of starting over with default settings.

Changes in build 104, 107

Support for MacOS Catalina was added.

Changes in build 91, 93, 94, 95

Dropbox support has been added. Choose Dropbox… from the File menu. Click the help button in the Dropbox window for more information.

New sample ebooks are included.

Stockfish 10 64bit is the new default engine.

$GAME$ error fixed when opening ebooks by clicking on them. (Windows)

Fixes “top candidate only” bug seen in some Windows 10 machines. (Windows)

Changes in build 87, 88

The MacOS Mojave issue is fixed. (The popup to edit candidate moves would disappear.)

New sample ebooks are included.

Stockfish 10 is the new default chess engine.

Changes in build 80 and 81

For Macintosh, the DMG file delivering the app is now “signed” and the app no longer stores the product key inside the app which should make Apple’s new version of

Gatekeeper happy. Gatekeeper in some cases would quarantine the Chess Openings Wizard app causing it to fail to open the Pedigree and ECO code databases.

A shortcut key of Control-Option-R on Macintosh and Ctrl-Alt-R on Windows will allow an ebook to be reset to its default settings and sizes. This is helpful if an ebook opens but is completely off the screen due to removing an extra monitor.

Changes in build 69, 75

The diagram settings are correctly saved.

A new option to remove the diagram’s frame was added.

Added arrows to show the last move made (optional).

Fixed issues with garbled diagrams when opening new windows on Windows 10 (certain graphics drivers).

Changes in build 67, 68

The size of the candidate moves can be adjusted.

The Pedigree ribbon is oriented sideways so that it is easier to compare different candidates.

The diagram prompts for underpromotions when moving a pawn to the eighth rank.

The correct promotion piece is drawn when clicking a candidate move that promotes a piece.

The program is smarter about saving the state of windows, including moving an ebook to and from  Windows/Macintosh and to and from computers that have multiple monitors.

More shortcut keys have been added to the menus. (Leif W, Stephen K)

Speed Learning was added. (YouTube video here)

Bug with board names longer than 41 characters fixed.

The selected square no longer stays selected when dragging a piece.

The maximums for nodes in EPD analysis to 2,000 (which is in millions of nodes) and 1,000,000 for seconds. (suggested by Bogg)

Changes in prior versionsResolutionSpotterPro
Font size of comments can be adjusted.Changed in build 60, 70 PE
More shortcut keys have been added.Added in build 62 P
Speed learning addedAdded in build 62 Pro P
Mac and Windows default to high speed piece movement.Changed in build 62 and beyond PE
Piece speed and diagram type (square color, font, etc) can be adjusted.Changed in build 60 P


The January overhaul of the training wizard can give full credit when making a right move after making a wrong move.Hud D.Win/MacPEhighfixed in build 192
The option to “Do not import duplicate comment lines” is working for PGN headers but not for embedded comments.Mark G.PElow
Game window has no way to flip the boardLes B.Win/MacPElowfixed in build 192
Some of the Alt key shortcuts in the menu do not work.Gregg S. Mark G.WinPElow
Mac Sonoma draws ebooks in an unusable wayfixedJames C.MacPEhighfixed in build 176
iOS and some Android versions fail to accept promotionsfixedWalther L. Steve B. Dave G.iOS, Androidhighfixed in build 176
Training window too tall to fit on low resolution monitorsfixedSteve B. Marcos S.WinPEfixed in build 177
Multimedia recording flips when recording with Black at the bottombugMikeWin/MacPMfixed in build 192
Read Only ebook status not savedcheckingNarcyz K.PE?low
F8 does not go back one ply in build 160fixed in build 167Rale W.Win/MacP/E?fixed in build 167
Applying diagram marks and then clicking on past move fails to save marks.Pavel K.Win/MacEMMay 2023
Importing PGN intermittently locks up the apptested with 750,000 gamesKeith K.WinP/Efixed?
Setting First Time Credit to 1 behaves as if full credit is givenDave H.Pfixed in build 192
When monitor is scaled to 150 percent, pre training window is too tall for the screen.fixedGary R.PElowfixed
Does not restore selected diagram colors when restartingFixed in build 141Justin A.WinPEfixedfixed
Board name does not display after setting up a positionMike L.Win/Mac
Dropbox uploads limited to 150MBFixed in build 167Marc L John J(all)PEhighfixed
Big Sur on Intel Macs failsfixedMac Big Sur on Intel (M1 Silicon Macs are okay)PEfixedfixed
Engine server continues analyzing after Android disconnects, using 100% CPUFixed in build 8.Rafa M.WindowsEngine ServerhighFixed in build 8
Importing 2,500 games crashestested with 750,000 gamesCelestino J.MacPEhigh
Importing PGN does not color code noveltiesFixed in build 115-120Keith K.Windows/MacPEhighFixed in build 119.
Engine name and path is limited in lengthFixedJames C.WindowsPEmediumfixed
EPD analysis fails after a large number of positionsinvestigatingNavid M.MacProhigh
PGN import slows, increases memory usagefixed in build 120Navid M.MacProhighFixed in build 115
Make Paste PGN behave like importing PGNcould not duplicateIlyas A.WindowsPEhighNot an issue
Error message and possible crash with Mac High Sierra – Use the Candidate menu instead of the dropdownFixed in build 86.Timothy R.MacPEhighFixed
Double clicking a document when the program is running causes two copies of the program and $GAME$ Assertion errorFixedPhil T.WinPEhighFixed in Pro build 91 and beyond
Backsolving a position with a blank rate when “Ignore blank rate symbols” is checked gives the wrong Informant symbol.FixedBernd H.WinPhighFixed in build 111.
‘G’ indicator of loaded game not workingFixed in build 119Tom R.Win/MacPEhighFixed in build 119. 
Setting up an illegal position (without a king) causes a crashBugHud D.Win/MacPEhigh 
Under-promotions not workingFixed in build 86.MikeWinEhighFixed
Pasting engine analysis needs a carriage return after itFixedRon T.Win/MacPElowFixed
Add Informant synching from legacy versionAdded in build 158Ron T.WinPhigh fixed
Make move order searches like legacy versionFixed in build 124ElirubWin/MacPEhigh 
Diagram is distorted when first opening an ebookFixedMike B, Raimund K.WinP, Ehigh Fixed
Importing games with no result gives incorrect backsolved Informant ratesFixedsagisagWinPhighFixed in build 111.
Selecting speed learning positions causes multiple confirmation windows.Bug – duplicated with customer dataHud D.Win/MacPhigh 
Mac Stockfish 7 crashesStockfish 10 replaced earlier versions.Celestino J.MacP, EhighFixed in build 91
cannot create a swap chain for ‘TCanvasD2D’Not reproduced, likely a graphics driver problemDaniel G.WinElowAssumed graphics driver issue
Crashes when candidate drop down button is clickedFixed in Catalina versionsJon G. A.MacEhighFixed
UNIQUE constraint error when adding duplicate positions to speed learningBugMike at BookupMac/WinPlow 
Mac Finder won’t open the app when a document is double clickedLimitation – the documents must be opened from within the appJacques P.MacP, Elow 
Backsolving freezes on start with sample data (Polar Bear ebook)BugEric O. Phigh 
Find games with this move order – doesn’t fill in movesFixed in build 124Eliezer R. Phigh 
Mac version beeps when pressing right arrow key for movesBugJacques P. Phigh 
Does not use MasterChess 8000 files.Design decision – workaround is to export all games to PGN. A new version of MasterChess will likely be the ultimate answer.  Plow 
The candidate area can lose focus and won’t react to arrow key navigation when this happens.Bug.Jacques P. Pmedium 
Only the top candidate move is played when clicking on other candidate moves. Windows 10Fixed.Geoffrey B. Colin P.
David M.
Lazaro M.
 Windows 10PhighFixed in build 91
The splitter bar below the past moves pane also moves the top splitter bar.Bug.Stan R.
John G.
Window menu is not populated. Harish S.    
Creating a Speed Learning set with named positions causes a dialog window to appear for each name. Fixed.Hud D P Fixed in build 111.


Show how many positions trained out of the entire book when done training.David K.low
In Program Preferences the button to change the diagram export file/folder does not work.lowfixed in build 190
Have the training wizard ask whether to reset training in the current set of played positions when a new candidate move is added.Mike L.lowadded in build 183
Show bookmarks as a table of contents.Carl B.low
Improve scrolling of menu items on touchscreensGregg S.low
Add a way to have Stockfish add candidates that improve on existing candidates. When adding a new candidate, have the resulting position assessed by the engine for backsolving.Ron T.low
If the ebook has Black at bottom, have the setup new position window also have Black at bottom.Ken W.lowfixed in build 183
Add training settings that would Continue If User Has a Candidate Marked {red, yellow, green}
Stop If Computer Would Play a Candidate Marked {red, yellow, green}
Greg U.low
Add themes, color choices for window backgrounds.Wane I.low
Allow multiple Dropbox files to be uploaded at once.Kent O.low
Have the novelty finder add the engine’s best move, even if it’s not a leaf node.Ron T.low
Add back the ability to mirror and reverse the color of a positionJeremy F.low
Import ChessBase MyMove repertoireRichard C.low
Support separate numeric assessments (manually assigned and backsolved) which will expose blunders in games that would otherwise be backsolved by the leaf node.Stephen R.low
Add more colors for diagram arrows, square marksStephen R.done
Add back option to use regular letters for notationAnthonyLow
Bring back Speed Learning storage sets with “right, wrong, skipped” results (prior to 2016)Stephen R. Low
Allow PGN to import comments only for existing positionsJames C.Low
Add optional sound effects for the movement of the piecesErnesto D.Low
Allow PGN import to ignore [% commandsMike L.Low
Add back saving the diagram to a BMPRay B.LowAdded in build 187
Allow precise RGB values for board colorsMichael T.Low
Allow texture choices for board squaresMichael T.Low
Add dark mode themeAl M.Medium
Refocus candidate move pane after using VCR buttons so that arrow keys work more oftenAlbert S. Mike W.Medium 
Add limit to the number of moves trainedPete Z.MediumAdded in build 124
Add button “restart training” to restart the last session with the exact same settingsPete Z.MediumAdded in build 124
Add auto update using Inno Setup’s /SP- /silent /noicons “/dir=expand:{pf}\My Program”Mike L.Low 
Have engine pause when EPD analysis finishesHud D.Low 
Add magic hand to training modeMike L.Low 
Add the C.A.P. databank (aka “Joy of Chess”)Steven K.Low 
Add algebraic hints to the borders of diagramsAdolfo P. P. Clive D. Mike W.LowDone
Add 3D chess boardRon T.Low 
Have the Enter key handle OK buttons.Jacques P.Low Some done.
Add back the ECO printing functionGerald G, Jim R, Calvin C. Randy S.Low 
Add move guessing to the diagram (clicking on ‘to’ square) as in ChessBase.Jacques P.  
Add a way to play a game against the engine from any position.Jeremy  
Have EPD engine analysis ignore nodes when set to zero.BoggLow 
Add option to Backsolving to ignore blank numeric assessmentsBoggLow 
Add Speed TestingJim GHigh 
Add Pro function to export lines as individual games (as in legacy)Bolvar G
Valet W
Medium Done
Add candidate font size adjustment to Express Mac version (Windows done)Serge D, Tom RHighDone
Fix Find Games with this move order (Express version)Tom RHigh 
Add command to synchronize Informant symbols based on numeric assessments (Pro version)sagisagMedium Done
Add command to Show All Move Orders (Pro and Express versions)Amoranemix, Michel L.Medium 
Program will run two instances, creating error messages for the shared $GAME$ database.Sandy S.MediumFixed in build 91
Program has to be killed with task manager if it cannot open an ebook from the last session.Randy MMedium Fixed
Add ability to select multiple PGN files for importSteve SMedium 
Add arrows and square highlightsMike L. and othersLow Added in build 141
Add rate symbol synchronization with numeric assessments with ranges higher than 100 for ++–Ron T.MediumAdded in build 158
Option to eliminate “Load Next Named Position” window when trainingHud D.Low

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