I’m guessing you had updated to CIS using the same CFP location? That location refers to the quarantine folder or “Virus Vault” of CIS. Detected items are stored there in a special format where they can’t do any harm and COMODO has denied all access to that folder for safety reasons. It shouldn’t be detected.
Is CIS/CAVS detecting this or another AV? Can you give us a little more information?
If you have a virus or malware in Quarantine Items in Comodo Internet Security, Then some virus/malware scanners might scan these areas and still believe you are infected but your not.