.chm navigation cancelled and app-v

By | 3rd October 2012

The good old message about .chm “Navigation to the webpage was canceled. What you can try: Retype the address.” has got me again!

I’ve been completely sure that I’ve nailed it pretty well with the following MS KB – http://support.microsoft.com/kb/896054

But it turns out there are even more things that you can dig into.




My app is a 64-bit one and has been calling the 64 bit hh.exe, I pretty much though that the registry settings I’ve applied must have nailed the security settings:


<REGKEY HIVE=”HKLM” KEY=”SOFTWARE\Microsoft\HTMLHelp\1.x\ItssRestrictions”>




But they failed to work, so I remembered there has been a neat feature with registry redirection that sealed the deal:


<REGKEY HIVE=”HKLM” KEY=”SOFTWARE\Microsoft\HTMLHelp\1.x\ItssRestrictions” NOREDIR=”TRUE”>







The NOREDIR attribute is optional and new in version 4.6 and defaults to FALSE when not present. Allowed values are TRUE/FALSE

When working on a 64-bit OS, registry values set using the OSD support redirection, just as the application normally would. Setting NOREDIR to TRUE tells the client that these registry settings being defined here should not be redirected as they normally would be.Normally you do NOT need to set this to run x86 applications on x64. This is simply an override in case you should need it.

P.S. Non app-v related .chm failure checklist – http://www.helpsmith.com/chm-cannot-be-displayed.php