Windows xp sp3 ie 7 Avast antivirus. Computer was compromised with many virus, malware. Format and reload is not an option. Avira on a boot cd scans clean. Malwarebytes, Spybot, Webroot, all come back clean. Mcafee free online scan now comes back clean. Hijack this is clean. Sophos, Rootkit Revealer show nothing. Avast keeps giving the following warning that a file in the temporary internet directory contains the html-iframe.inf. and to continue, you have to delete the file.

Trendmicro will not run online. Windows firewall was compromised, but has been fixed. Only legit services are running. No un-necessary startups. Netframework 3.5 update will not install.

Any help appreciated.