I have followed the instructions found in
http://support.microsoft.com/kb/896054 under 'method 1 Modify the
ItssRestrictions registry entry to enable a specific Web application' and it
seems to work for Windows XP when the CHM file lives on a network resource
being accessed by either a Mapped Drive or UNC path. It also seems to work
for Windows 2000 only if the CHM is accessed using a mapped drive. It does
not work for Windows 2000 if the CHM file is accessed using a UNC path.

The only way I can access a CHM from a network resource using a UNC path on
Windows 2000 is by using 'Method 2 Modify the ItssRestrictions registry entry
to enable a specific security zone'.

I would prefer to use method 1 for Windows 2000 since it's more secure, does
anyone know if this is possibile.

Thanks!