Help File Gives Action Canceled Error

Opening Beyond Compare's help file can give the error message "Action canceled" when Beyond Compare is installed on a network drive.

This error message shows up after installing Security Update 896358 (MS05-026: A vulnerability in HTML Help could allow remote code execution).  This security update prevents .CHM help files from displaying when they are located on a network drive.  However, you can edit the registry to add Beyond Compare's help file to the "allow list".

Warning:  Editing your Registry can be dangerous!  Please do not attempt this if you are not confident of your skills in this area.  Make a backup of the Registry before editing it.

From the Start menu, select Run and type "regedit".  Then, create the following registry keys, replacing "BCPath" with the Beyond Compare program folder (eg. "C:\Program Files\Beyond Compare 4"):

[HKLM\SOFTWARE\Microsoft\HTMLHelp\1.x\HHRestrictions]
"UrlAllowList"="BCPath;file://BCPath"

[HKLM\SOFTWARE\Microsoft\HTMLHelp\1.x\ItssRestrictions]
"UrlAllowList"="BCPath;file://BCPath"

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