If you own VB/VS 6.0 Professional or Enterprise editions, try this:

1. Unistall VB6.0 or VS6.0, then ensure to remove all files and folders
2. Clear registry node:
- HKEY_CURRENT_USER\Software\Microsoft\Visual Basic
- HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Visual Basic

3. download my free tool VS6.0 Installer 2.1 (see my sign)
4. install VB6.0 + SP6 + MSDN (optional) using VS6 Installer steps

Let me know.