Hi, Jay -
Rule out the obvious first: Is Excel installed on your friend's PC?
I'm not an Excel via OLE expert by any means, but the two lines of code you supplied don't look right to me. I believe Count is a property, not a method, in the Excel Object Model, so shouldn't "xxxx.Count()" instead be "xxxx.Count"? Same for Worksheets...it is a collection, so shouldn't the worksheet count be coded as "xxxx.Worksheets.Count"? I know you can reference a particular item within a collection like this: "Wookbooks(1).Worksheets.Count", but it is not clear to me what you are attempting to accomplish.
Have you put your OLE code within Try...Catch blocks? I have found that using Try/Catch to handle and examine and display info from OLE exceptions is very helpful in debugging MS Office via OLE.
HTH
-john