Another quick "Just in case I did something stupid" style of check (I do those ALL the time since the chances of me doing something stupid increases exponentially as the amount of caffeine in my blood stream drops).
Can you open the Excel file manually on your box? If so, what happens? Are there any particular prompts for conversion or other such things that might mess up a data access driver?
Also, what's the data in the file? Is it coming through correctly with proper data types etc?
One final check:
Make sure there's not a copy of Excel sitting memory resident in the background that MIGHT have hooks into your excel file.
I'm scraping the bottom of the barrel here but with a message like "unknown error from external driver" to help us, I'm kinda at a loss.
