I have a number of PC's in my office that are exhibiting strange behaviour. The svchost.exe (netsvcs) process is consuming all of one of the machines quad cores. If I stop the Windows Update Service the process ends and the machine goes back to running normally. If I start the service back up the process runs wild again. It's occuring on Win7 machines, I wiped the C:\Windows\SoftwareDistribution folder, no luck. If I manually search for windows updates it starts up the svchost process and goes back to using all CPU.
How can I find out why the Update service causes this?