Slow Computer - Virus?

[Millandy]

Our computer is a seven year old Dell, and was running perfectly well until I restarted it about a week ago. Upon logging on, the computer tells me that the CPU usage is 100% all the time, and this never changes. The computer is very, very slow - it takes fifteen minutes to open one single folder.

I thought this was a virus so I have tried to do several scans. Nothing has been picked up, but I am aware that if I have accidentally downloaded a virus my computer won't pick it up, as I authorised the download. However, I haven't downloaded anything recently. The scan took four days then the computer shut itself down without completing it.

I am thinking the only option is to get a professional opinion, but I just wonder if this really is a virus, or something else. Thanks for any help. :)

[1234567billy]

what programme/s are taking uo the 100%.
sometimes virus protectors can cause havoc.

[Ethel]

Look at your task manager - that should give you some indication as to what is eating up your CPU.

Have a look at the programs that are starting automatically on boot up.

Start - run - type

msconfig

Google each and every thing in the list - untick it if you know what it is and don't need it to start automatically. Printers and other peripherals don't need to be there, and the only programs you need to start up straight away are your firewall and anti-virus.
If you don't recognise anything, leave it alone.

Do basic maintenance - clear out your temp files, and defrag.

Is there anything you have found doing these things that has made a difference or is worrying?

[Jugglering]

Have you got two anti-virus programs running ? If so, you will need to remove one of them as this often causes pc's to go very slowwwwwwwwwwwwwwwwwwly....

[Millandy]

It just says "Winlogon.exe" which is taking up about 99% of the CPU all the time.

[kaw69]

Sounds like the problem I had last year, it is the registry which can be very tricky to mess with if you don`t know how it works.
I used Google to find a cheap solution and I took the 10bit.com free progamme. Ok I had to purchase a small item off their list but as well as the purchase it gave me an unlimited (forever) use of of their Advaced Windows Care V2 programme which I use every couple of weeks and it always amazes me how much stuff it detects and fixes

Use this link and click on the Free with Trialpay

http://www.iobit.com/AWC2ProOnePage.html?Click ID=clfiwekpxsskf4kxznvvaks7iwsvwivs4ezl

Good luck

[Ethel]

If your winlogon.exe is in the folder C:\Windows\System32 then is the proper and necessary part of Windows log in.

If it is anywhere else it is a trojan.

If it is in System32 then it has somehow corrupted and you need to repair/reinstall it.

But first, find out where it is.