I post this not as an expert on the MS-Windows system but as means of offering two options from the Windows Knowledge Base to get your Automatic Update facility working once more BESIDES re-loading XP all over. This Knowledge Base article is extremely hard to find yet resolving the matter is relatively simple as I found.
I post these since I note most Administrators are not aware of this means of getting "Automatic Updates" operational again and sugget re-loading XP.
I wld suggest if you are not slightly geeky when it comes to computers that you would be best calling on a friend who is computer literate to enter the commands below.
Be aware that if you let Vundo inherit your computer for too long, it may be too late to repair some of the MS-Windows files damaged. In my instance, Malwarebytes Anti-malware did a grand job of catching the infected registry files (all 27 of them) and fortunately my Kaspersky Anti-virus tool captured the trojan files. This left me with the Windows "Automatic Updates" utility as dead as a dodo.
Following step 1 below resurrected my "Automatic Updates". A quick word on making the Automatic Updates operational again. Aside from following the below procedure (step 1) I found having applied the steps the Automatic Updates utility would not start. Be aware that to start Automatic Updates with inclusion of the files on which it is dependant requires stopping it first. Simple OK - well not quite. Following registering the Wups2.dll file and trying to start the service from the Run prompt using the command "net start wuauserv" in Step 1 below, it failed to do so. I found that the only foolproof method of stopping and starting the service so that the registered file can update is through Control Panel > System > Automatic Updates and stopping or starting the service there. Thus insert this instruction to start and stop the service rather than through the Run prompt below and you will be in business (I hope). Ironically, I found my service still running despite running the command "net stop wuauserv" which should have halted it! Hence this advice.
The MS-Windows Knowledge Base article follows - best of luck!!
This problem occurs because of how the Windows XP repair operation replaces Windows system files. When you repair a Windows installation by using a Windows XP CD, the repair operation performs both of the following operations: It replaces all the Windows system files with the corresponding files from the CD.
Note This includes the Windows Update files.
It restores the Windows registry.
The latest version of Windows Update includes a file that was not available in the release version of Windows XP. This file is named Wups2.dll. Therefore, after the repair operation is complete, the following situation exists: The Wups2.dll file remains on the computer.
The registry entries that correspond to this file are missing.
Because the registry files that correspond to the Wups2.dll file are missing, update installations are unsuccessful.
Back to the top
To resolve this problem, use one of the following methods.
Back to the top
Method 1: Register the Wups2.dll file in Windows
To register the Wups2.dll file in Windows, follow these steps:1. Stop the Automatic Updates service. To do this, follow these steps:a. Click Start, click Run, type cmd, and then click OK.
b. At the command prompt, type the following command, and then press ENTER:
net stop wuauserv
2. Register the Wups2.dll file. To do this, follow these steps:a. At the command prompt, type the following command, and then press ENTER:
Note For a computer that is running Windows XP Professional x64 Edition, type the following command, and then press ENTER:
b. Click OK on each verification message that you receive.
3. Start the Automatic Updates service. To do this, type the following command at the command prompt, and then press ENTER:
net start wuauserv
4. Exit the command prompt. To do this type exit, and then press ENTER.
Method 2: Download and install the Windows Update Agent
To resolve this problem, follow these steps: 1. Download the appropriate version of the Windows Update Agent to a known location. To do this, visit one of the following Web sites.
AgentWindows, x86-based systems
Windows, x64-based systems
Windows, Itanium-based systems
2. Click Start, click Run, click Browse, locate the file that you saved in step 1, and then click Open.
3. Add the /wuforce switch to the end of the run command, and then click OK. For example, the run command may appear as the following:
4. Click Run.
5. Follow the steps to complete the wizard.