A while back I noticed on one of our laboratory computers (Windows 7, very little extra software installed) that the network connection icon in the system tray would claim that it had no network connection, even though it did. This issue would go away after the computer was rebooted, but would surface again the next time I looked at the computer (a few days later).

Upon opening the Network and Sharing Center I am shown an actual error message, but not one that seems to give me a lot of information about what the problem is. In the place of the usual information about network adapters and whether you are connected to the Internet it simply says: "No more threads can be created in the system."

The Event Viewer shows hundreds of events from different services also with the same message. "Volume Shadow Copy Service error: Unexpected error calling routine CoCreateInstance. hr = 0x800700a4, No more threads can be created in the system."; "The WinHTTP Web Proxy Auto-Discovery Service service failed to start due to the following error: A thread could not be created for the service."; "The IP Helper service terminated with the following error: No more threads can be created in the system."

As far as I can tell, this message seems to mean that there is some sort of resource leak in Windows where something is creating a large number of threads and those threads are not being killed off? I've tried restarting WMI and several services related to networking, without avail. Can anyone provide more information on what "No more threads can be created in the system" might mean and what I might be able to do to fix the issue? Currently the only solution appears to be restarting.