I believe this may be due to memory configuration issues, any luck with a fix?
I'm running MSSQL 2005 Standard Edition ver. 9.00.4035.00 (SP3) on Windows Server 2003 32bit and a similar problem arises in a number of cases, including OPENDATASOURCE and OPENQUERY towards Access databases and Excel sheets, BULK INSERTs with linked servers and CLR procedures: pretty much everything that can be classified as an external data source, involving the use of external dlls. This is slowly driving me mad, looks like it has something to do with memory management, although I am currently using AWE and reserving ~6 GB for the sql service... Things work fine until the process reaches a certain amount of allocated memory, which is usually around 4GB but can sometimes be ~1.5GB; unfortunately, restarting the service appears to be my only option at the moment :-(