trojan downloader need help urgently

will anyone please be able to help me with this problem:
i have been infected by various spywares and keyloggers such as net.net and "this is not adware" which were easy enough to get rid of however the big problem is i have a Trojan-Downloader.Win32.Small.dxm which through just about all of the dlcore.dll files i have the irrittating thing is that it is in the winlogon.exe file which is preventing the computer from logging out or shutting down without a fatal error so a system restore will no work as it cannot correctly restart.
i have tried many anti-spyware and virus programs which remove all other infections except this one which will not quarantine or delete. i have tried killbox which failed also. i have hijackthis also so can run it if it is required because i cannot make out all of the nasties. it has been like this for about a week and is only a 2month old pc.
thanks in advance for any help
seb

 

Welcome to MajorGeeks.com, please follow the steps below:

- Run ALL the steps in this Sticky thread READ & RUN ME FIRST Before Asking for Support

• Make sure you check version numbers and get all updates.

After doing ALL of the above you still have a problem make sure you have booted to normal mode and run the steps in the below link to properly use HijackThis:

Downloading, Installing, and Running HijackThis

Make sure you also rename HijackThis.exe as suggested in the procedures. Use analyse.exe for the new name. This is very important due to some new infections going around.

When you return to make your next post, make sure you attach the following logs and that you have run these scans in the following order too:

• CounterSpy
• AVG Antispyware Log - ONLY IF NEEDED you were not able to run CounterSpy
• Bitdefender - from step 6
• Panda Scan - from step 6
• runkeys.txt - the log from GetRunKey.bat
• newfiles.txt - the log from ShowNew.bat
• HijackThis