Hotfix for 'W3wp.exe process consumes 100% of CPU' on Vista or Windows Server 2008

“You run Internet Information Services (IIS) 7.0 on a computer that is running Windows Vista or Windows Server 2008. The computer has more than 64 GB RAM. Unexpectedly, the W3wp.exe IIS process consumes 100% of CPU resources. Therefore, the computer experiences low performance,” Microsoft reveals via KB975798. “This problem occurs because the highest memory address […]

“You run Internet Information Services (IIS) 7.0 on a computer that is running Windows Vista or Windows Server 2008. The computer has more than 64 GB RAM. Unexpectedly, the W3wp.exe IIS process consumes 100% of CPU resources. Therefore, the computer experiences low performance,” Microsoft reveals via KB975798. “This problem occurs because the highest memory address of the kernel mode HTTP driver (Http.sys) is defined as 64GB.” According to Microsoft, customers would have to be running Windows Vista Service Pack 1 (SP1), Windows Vista Service Pack 2 (SP2), Windows Server 2008, or Windows Server 2008 Service Pack 2 (SP2) in order to be affected by this problem. A supported hotfix is available from Microsoft, intended to correct only the problem that is described in this article.