This problem is happening on a fresh installation of .Net Server 2003. There's no virus checker running.
There's no explicit pinning in our code - the framework Socket implementation pins the buffers before issuing the IOs to winsock. Our application is a fairly big one, with multiple appdomains and heavy CPU/memory usage. We're working on a small demo program to reproduce the problem. I'll post this if and when we can isolate the situation. Thanks for the suggestions/ideas so far. =================================== This list is hosted by DevelopMentorŪ http://www.develop.com Some .NET courses you may be interested in: NEW! Guerrilla ASP.NET, 17 May 2004, in Los Angeles http://www.develop.com/courses/gaspdotnetls View archives and manage your subscription(s) at http://discuss.develop.com