BleepingComputer.com: Residual effects from Agent.HZ trojan

My computer was infected by the Agent.HZ trojan a couple of days ago. I have done the following:

1- detected and deleted the malware using Avira
2- executed System Restore, rolling back my system by 2 weeks
3- ran CCleaner to attempt to scrub any residue from the registry
4- ran Trend Micro House Call in an attempt to detect more viruses -- result was negative.
5- updated Avira, ran system scan again -- result negative

Currently, I can use my computer for about 45 minutes to an hour without problems. Then,usually if I'm in either Firefox or MS Word, text fields become garbled (esp. in Word) or are left blank (esp. the tabs in Firefox). Once these troubles begin, the stability of the entire machine goes down hill. Specifically, I am unable to open Task Manager or, upon closing Firefox or Word, cannot reopen them.

The usual error messages indicate that whatever program I'm trying to open failed to load. However one time I received an error message indicating I had insufficient RAM and hard drive space to open the desired program. I then went to My Computer and looked at the properties of the C drive. The pie chart indicated my drive consisted of 0 bytes (0 bytes used, available, etc.) I opened the drive and randomly selected a folder and looked at its properties -- again, the computer indicated the folder contained 0 bytes even though there were other folders and files in it.

What do I need to do to fully rid my computer of this malware?

Thank you for your help.

This post has been edited by Budapest: 06 December 2010 - 11:39 PM
Reason for edit: Moved from XP ~BP

Oh, yes. And I'm using XP Tablet Edition, SP3.

Ok, I seem to have fixed it by using Spybot Search & Destroy.

Sorry for the delayed response but staff members are all volunteers who assist members as time permits. Unfortunately, this means sometimes a topic thread will get overlooked when requests for assistance get backed up.

mvps.org is no longer recommending Spybot S&D or Ad-Aware due to poor testing results. See here - (scroll down and read under Freeware Antispyware Products).

Ad-Aware has even been placed into the Installers Hall of Shame for bundling and pre-checking Google Chrome during the installation. Also read Lavasoft Turning to the Dark Side? writtne by a former volunteer (now a MVP) who provided support for Ad-Aware but no longer uses the program.

As for Spybot S&D, most people don't understand how to use TeaTimer and that feature can cause more problems than it's worth. TeaTimer monitors changes to certain critical keys in Windows registry but does not indicate if the change is normal or a modification made by a malware infection. The user must have an understanding of the registry and how TeaTimer works in order to make informed decisions to allow or deny the detected changes. If you don't have understanding how a particular security tool works, then you probably should not be using it. Additionally, TeaTimer may conflict with other security tools which do a much better job of protecting your computer and in some cases it will even prevent disinfection of malware by those tools.

More effective alternatives are Malwarebytes Anti-Malware and SUPERAntiSpyware Free.

Although you say your issue is resolved, I recommend you perform scans with the above two programs.