Run the System File Checker (with the "Scannow" parameter).
Description of System File Checker (Sfc.exe)
[URL="http://support.microsoft.com/kb/310747"]http://support.microsoft.com/kb/310747[/URL]
-or-
Expand the DLL file from the source manually.
How to expand Windows XP files from the installation disk:
[URL="http://support.microsoft.com/kb/888017"]http://support.microsoft.com/kb/888017[/URL]
>> Stay informed about: oleacc.dll