I have some expiernce when using HJT but when I tried to run it on this computer (my old laptop), it stops and freezes on..O15 Trusted zone numeration. I was wondering if someone can help me fix this in order to finish a scan and post a log. Thank you.

Hi :

Some further info might be helpful, such as the version NUMBER of HijackThis
you are trying to complete a scan AND the NAME of the Operating System of
the "old" laptop !?

There is new malware being developed nowadays that will affect running a
scan using "hijackthis.exe", requiring a "RENAME" of the program to something
like "nothijackthis.exe", etc .

The version of HJT i am using is 1.99.1 and the OS is windows xp home edition. sorry for the long reply, I was at school and forgot to bring it with me.

Yes some malware can hide certain entries in a log while other types may keep the program from running altogether so renaming sometimes helps. Open the HijackThis Folder, find the HijackThis.exe file, right click on the file and select rename. Type Analyze.exe and hit "Enter". Double-click on Analyze.exe (which is still hijackthis) to run the program. If needed change the .exe to something else such as .bat, .com, .pif, or .scr. Example: Analyze.bat or Analyze.com

If that still does not help, try this:
Download DelDomains.inf
alternate download
1. Save it to your desktop.
2. Right-click DelDomains.inf and select: Install (no need to restart).
3. You may not see any noticeable changes or prompts - this is normal.

Note: The DelDomains.inf file will remove ALL entries in the Trusted, Restricted, and Enhanced Security Configuration Zones. Any entries that you had will need to be entered again. You will have to reimmunize with SpywareBlaster, and/or Spybot after doing this, and reinstall IESpyads if you use any of these programs.

Then try scanning again with HJT.