is it a virus or a bug or what??!!

Viruses and worms
1

Hi!

I have a problem with avast and I dont know if it is a virus or not. no idea what to do :-(. a few days ago the computer stopped recognizing the avast icon on the desktop. tried to uninstall it from control panel-add/remove programs, and it wouldnt let me. it tries to install it always. then, tried to install a different antivirus, it wont let me do it. then tried to delete all the avast files from the computer and it says that it cannot delete file ashshell.dll. tried to do restore the system to a month ago, it says not possible. checked all the .exe files that i have on startup, none of them seems to be a virus. WHAT SHOULD I DO???

2

What Operating System are you using ?

Have you changed anything that coincided with the disappearance of the avast icon ?

Are you talking about the ‘a’ icon in the system tray to the left of the clock or the Actual Desktop shortcut ?

Why wouldn’t it let you uninstall, what error or warning is/was given ?

3

i can’t remember exactly when the avast icon disappeared, but the last thing i downloaded on my computer was a program called mestre-c (a chemistry program). i dont know if it’s got something to do with it. before that, i hadnt downloaded any program in a long time. the “a” icon in the system tray has disappeared and the desktop shortcut is there but it doesnt open, it is not recognised by the computer. also, when i try to uninstall avast from the control panel, i click on “remove program” and it starts installing it instead, even though it is already installed :-(. so it doesnt even give me the option of uninstalling.

4

This may be an attack on avast (and other AVs).

Bagle Rootkit variant:
See http://forum.avast.com/index.php?topic=26554.0
http://forum.avast.com/index.php?topic=25941.0

These seem to have the best results with this type of attack and are reasonably user friendly.
http://research.pandasoftware.com/blogs/research/archive/2006/12/14/Rootkit-cleaner.aspx
http://www.f-secure.com/blacklight/try_blacklight.html

5

thanks a lot for your suggestions. unfortunately, i run both anti-rootkits, found 200 files that i removed from the computer, but the problem still exists :frowning: . found a file in the avast webpage that allowed me to uninstall avast, but i am still not able to install any other antivirus. have tried avg, norton, mcafee :-(. also, my wireless has been disabled now. any more suggestions? thanks again

6

Did you read both of the topics I gave links for as that will contain more information. My inclusion of only two anti-rootkit tools was for speed, there are others.

Once you removed those you would need to try and repair or reinstall avast as elements might have been deleted.
Try a repair of avast. Add Remove programs, select ‘avast! Anti-Virus,’ click the Change/Remove button and scroll down to Repair, click next and follow. You need to be on-line to do this.

Also having got rid of some of this infection hiding other elements you may have some further success with other conventional tools.
If you haven’t already got this software (freeware), download, install, update and run it, preferably in safe mode.

  1. If using winXP AVG anti-spyware (formerly Ewido) Resident scanner during trial On-Demand after trial ends. Or SUPERantispyware On-Demand only in free version. Or Spyware Terminator Resident scanner.
7

Before installing any other antivirus, please, uninstall avast.
But if you’re deeply infected, maybe it will be easy and faster to restore backups you’ve done previously and just reformat the computer. 200 infected files is quite a lot!