Hi, I just posted this question in the MSMQ forums, see this link http://social.msdn.microsoft.com/Forums/en-US/msmq/thread/593253d4-52a0-4396-8517-9f3bacf22dd3 but I want to ask here for details about the Reliable Multicast Protocol. I have the problem, that the .PGM files generated by the protocol, are not always removed from my windows/system32 folder. This can lead to the situation, that my Windows 2008 R2 server, which serves a web page using MSMQ, is running out of disc space, which is not acceptable in an web environment. Now I think I could solve the problem, by correctly closing the MSMQ queues used within my application. So far so good. To get a better understanding of the processes that are happening on the system, I was wondering, why these files were not deleted when there is no process left that uses them? I guess that the recycle process of the IIS just killed the existing queue instances which leads to this situation. Is there any possibility for me to gain more control over these files? Is there anything like a 'garbage collection' that could be used? It would be great if someone can give me some more details on what happens in such a scenario. Regards WRalph