Hi,

We've managed to find a solution to the issue.

One of the issues was related to this, http://support.microsoft.com/kb/209805. Specifically in the registry, it looked like an unrelated update had deleted this dll "Msexcl40.dll" from the registry.

Microsoft ExcelHKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Jet\4.0\Engines\Excel

After we added it using "Regsvr32 c:\winnt\system32\msexcl40.dll" (with the correct path to the dll) the openrowset query worked fine.

Also we noticed that you needed to have SP4 for 2005 installed as well since we added the missing registry entry to two servers and one still only had SP3. After the SP update they both worked fine even though there were no notes in the SP 4 update relating to excel or access dlls.

Thanks