You may want to give a few more details about when, where, how, etc. you are getting the error.
MRPGetSupplyBranch appears to be a pristine function and is assigned to the CMFG dll on my release. Are you getting this error on your Enterprise Servers or Fat Clients? Since you are on Xe I assume you are not in the middle of an upgrade but have you applied any ESUs? If this function was introduced or had its DLL re-assigned in an ESU or was changed to either client only, server only or client/server than something there might be the issue. You can check OCMs but since this function appear to be client/server I doubt that is the issue.
You can do a DUMPBIN and see if that function is listed in the DLL where the process that is calling it is executing.
