all4naija:
First and foremost, uninstall the avast anti-virus and do a system restore to when you were not having the problem. On how to do system restore follow this LINK. If you don't have restore points in your system you can do the following.

1) Download Malwarebytes with another system and copy it to a USB flash drive.

2) Restart your infected system and immediately press and hold F8 key to enter Advanced options.

3) Select Safe Mode and press ENTER key.

4) At Safe Mode put your USB flash into the USB port and install the malwarebytes.

5) Run malwarebytes after installation and click scan now to scan your system.

6) Delete all found malicious software or virus and restart your system.

Please, report back to tell us what you experience after the instruction. Don't forget to copy out the error message or code you have been getting and post it here.

drss:

Pls how do I uninstall avast? I tried to uninstall it through the control panel but was denied access. Is there another way?

all4naija:

Yes. Download unlocker from HERE and install it. Go to your program Files directory in your C driver and look for Awil folder. Right-click on it and select unlocker. Cilck the drop down menu with 'No action'and select delete and click on to delete it. I t will take a lot of time before deleting everything. If it could delete everything it will alert you to reboot. That is it.

drss:
@all4naija I was unable to do what you ask me to do. Seems like my system is not responding to anyhting. It boot quite alright but its not showing any desk icons. What do you think is the problem?

all4naija:
Let see the image of your system posted here?

drss:

Blank screen. No desktop icons. Do I need to format the system and reinstall windows xp?

all4naija:
Okay. But you didn't boot into Safe mode as I told you before.

Restart your system and press F8. Follow the first instruction I gave to you in previous post. The one with the list. If you aren't not getting any result then follow the one below:

Press crtl + Alt +esc key to open taskmanager . Click File tab and type appwiz.cpl into it. Look for avast and right-click on it and select uninstall. Follow instruction screen to delete it.

drss:
@all4naija Done everything as you said. I installed the malwarebyte program in safe mode but it failed to initialize.
Below is the screen shot.
Avast security seem to the culprit. Its blocking programs from functioning.
I also tried to restore the system based on the steps through the link you gave me but when I clicked restore system, a dialoq box appeared searching for the program endlessly. The second image.

all4naija:
Okay. Restart your system and boot normal to your desktop.

1) Press Windows Key + R to open Run dialog.

2) Type msconfig into it and click on OK.

4) Click on 'Services' tab above and mark the little box close to 'Hide all Microsoft service' below.

5) Click on 'Startup' tab and click on 'Disable all' and then click on Apply. Click on OK to close configuration dialog.

6) Click Restart to restart your system.

7) Run malwarebytes and scan your system for malicious software.

8.) Delete all the issues found and restart your system.

9) Go to your Program file folder in C drive. Locate the Avast folder. Right-click on it and select unlocker.

10) Click the 'No action' menu and select Delete and click OK. Wait for it to remove all file from your system. It might require you to restart the system to finalize deleting of files.

drss:
Thanks for your help @all4naija Finaly! I got rid of avast security. The system is acting normal now. Though malwarebytes is still not openning.
The only problem now is that I can't access some programs. Anytime I tried it always say somthing like this: Windows cannot find 'C;\WINDOWS\system32\rundll32.exe', make sure you typed the correct name correctly, and then try again. To search for a file, click the start button, and then click search.
Anything you can help me with?

all4naija:
It is because you install it in safe mode. Uninstall the malwarebytes and download a fresh one and install it. Run it and scan your system properly.

Download a ccleaner and install it. Run it and click on the registry tool. analyze . After that click clean issues, next click don't save and click ok. Repeat it until it no longer find any issue.

What are the programs you cannot access?