Hi, I have a problem getting mpich2 to run on Windows Server 2012. We have a small set of servers successfully configured and running Windows Server 2008 R2 and MPICH2 without any problem. The error I get seems to indicate a problem in the authentication process.

"c:\Program Files (x86)\MPICH2\bin\mpiexec.exe" –validate

SUCCESS

"c:\Program Files (x86)\MPICH2\bin\mpiexec.exe" -host localhost nonmem.exe

Credentials for Lars rejected connecting to localhost Aborting: Unable to connect to localhost The credentials are correct and I have tried multiple user accounts with the same result. I don't think it's related but for what it's worth I have made sure that I have the same firewall settings for the mpich executables as on the 2008 R2 servers. I would appreciate any help in getting this solved. Thanks, Lars