The stub received bad data

I have a delphi app on an XP SP3 that talks to delphi com+ on windows 2000 server, has been working fine but now for one of the calls to the com+ it wo开发者_StackOverflow社区nt work and returns the error -The stub received bad data.Although 2 other calls to the com+ work fine.It passes values back to app and can do this for the other 2, thought it was to do with a SP2 issue but it has SP3 so thats that ruled out. No errors in eventvwr. Does anyone know why this would be? Fairly to new to delphi here so any help much appreciated.

Check if the COM method you are calling is using parameters marked with the [out] flag, and if so then check that you are not passing nil values for those parameters.