Plug-in does not register itself specifically for some IDE. It just
placed some records in registry, and if IDE support SCCI it should use
it. Please check this link to see where you should found SourceControl
support in VS 6.0
http://www.pushok.com/help/cvsscc/index.php?redirect=inst_plugin.htmAlso, are you sure that now you have right version (edition) of VS 6?
Could you access SourceSafe from it? We use VS 6 with our plug-in
without any problems (it itself written in VS 6).