Failure to create Program Groups on NT 4

Does anyone know why certain installations fail to create program groups on an NT 4.0 Workstation machine?

I have seen this happen with a few products, but currently I am having a problem with Powerbuilder 7.0 by Sybase.

Version 6.5 did the same thing to me, but it would at least continue with the install. 7.0 kicks you out.

All installs have been attempted while logged in as administrator.