How do I keep this error message from appearing upon start up

See this page for a description of the file, and check to see that it is not a "fake" version installed by malware.  Then you can try going to the Command Prompt and running the DOS command SFC  /SCANNOW to start the System File Checker and possibly replace a corrupted/missing file:

http://www.liutilities.com/products/wintaskspro/dlllibrary/oleacc/

You mentioned cftmon.exe in your tag, which is a part of the Microsoft Office suite and handles speech input.  I'm not sure how OLEACC.dll relates to this, but it is an OS system file.  I would recommend grabbing the OLEACC.dll file off of your XP disk (or you can get it from numerous sites online) and copying it back to where it's supposed to reside in C:\Windows\System32.  

http://support.microsoft.com/kb/810684

Buddy this can help you to solve the problem

jeebukarthikeyan:  That page indicates that it only applies to Win98.

Or download this:
http://www.dll-files.com/dllindex/dll-files.shtml?oleacc

FCPCTech, any feedback?

I had to dow a system restore in order to get the error message to disappear.  Thanks for all of your help.