Symptoms
Automic HTML Help will not be opened properly when installed on a non local drive.
Cause
Microsoft blocks opening chm files over network because of security reasons
http://support.microsoft.com/kb/896054
Resolution
Set this Registry Key to allow open CHM Files to be opened via Network
[HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\HTMLHelp\1.x\ItssRestrictions]
"MaxAllowedZone"=dword:00000002
For further Information please read the MS article above.