checkin policies in HKLM on 64-bit machines - need to go into Wow6432Node!
One thing you may have noticed in the MSDN docs or my blog is that if you're installing checkin policies, the registry value you add to specify that path to the checkin policy goes under the key HKLM\SOFTWARE\Microsoft\VisualStudio\8.0\TeamFoundation\SourceControl\Checkin Policies
There's a case where this isn't true, though - since VS2005 doesn't have native 64-bit support (it's a 32-bit application), it runs in WOW64 mode on 64-bit Windows. One of the implications of running in WOW64 mode is that you may not access the same registry keys as native 64-bit apps (1, 2).
This means that if you're installing your checkin policy's registry value into HKLM, you'll need to add a "Wow6432Node" part after "Software" to the path. That way, it'll be in the right place when we go to find the installed policies on the machine.
As an example, here's how you would install a MyPolicy assembly in such a situation:
reg add "HKLM\SOFTWARE\Wow6432Node\Microsoft\VisualStudio\8.0\TeamFoundation\SourceControl\Checkin Policies" /v MyPolicy /d "C:\some\path\MyPolicy.dll"
Note that since HKCU doesn't participate in the registry reflection, you don't need to add the Wow6432Node part to the path if you install your policy there. Of course, though, then it's only available to your user on that particular machine.
