I reinstalled Windows XP on a clients PC recently, and came up against an issue where I couldn’t update Windows using Windows Update. I then noticed that the PC had slowed down to a crawl. Opening up Task Manager, Processes and Sorting by CPU, I found that svchost.exe was consuming 100% CPU.
I tried killing the process, and retrying the updates, but svchost.exe was back to 100% as soon as I did.
Having searched around multiple forums for a long time, I finally found a solution which sorted the problem;
Firstly, download Internet Explorer 8 for Windows XP – http://www.microsoft.com/en-gb/download/internet-explorer-8-details.aspx
Once that has downloaded, install the hotfix KB2870699 for IE8 – http://www.microsoft.com/en-us/download/details.aspx?id=40119
Hey presto, problem solved. You can now use Windows update and install the 300+ updates that are required!