Windows cannot open the 64-bit extensible counter DLL aspnet_state in a 32-bit environment. Contact the file vendor to obtain a 32-bit version. Alternatively if you are running a 64-bit native environment, you can open the 64-bit extensible counter DLL by using the 64-bit version of Performance Monitor. To use this tool, open the Windows folder, open the System32 folder, and then start Perfmon.exe