I\'m trying to perform some memory profiling on an applications that is accumulating large amounts of memory.
I have found this tool (CLRProfiler): http://msdn.micro
You can use a commercial product like ants memory profiler (red-gate) or dotTrace (jetbrains).
Both are very easy to get started with.
If your project is set to build x86, then you have to use the 32 bit version, even if your OS is 64 bit.
Check out Redgate:
http://www.red-gate.com/products/dotnet-development/ants-memory-profiler/
You are probably using the wrong version!
The new (v4.0) version is at http://www.microsoft.com/en-us/download/details.aspx?id=16273, which is working well for me (and it's free).
If you work with W7 or Vista, start it as administrator (File->ContextMenu->Run as Administrator). As already said by others, also check out to use the correct version.