CFP Vista Home Premium, lost internet.

Installed CFP on a Vista PC, on a small home network behind a Linksys router. Lost all internet connectivity. This PC uses a wired connection. Another PC still connects wirelessly thru the same router, but without Comodo.

No fixes from other threads have helped. Even uninstalling CFP and doing a System Restore failed to get DHCP working again or allow internet traffic even with a fixed IP address. Is there anything I can do to repair this damage, short of reinstalling Vista? I can only imagine what an ordeal that would be.