Failed to Self Register OCX

Trying to install software (Sametime & IP TV) on Win2K Pc. Both report “Warning: File(s) Failed to self register”, and lists the files. For sametime the files are VpBase.ocx & Connect.ocx.

Software does not work as a result.

As this same warning happens with different software, I think my O/S is at fault, but open to any ideas.