Classic 2009SP1 Job Queue Saveas problem: SaveAs method of workbook class failed

Dear Experts,

I know that this is a very old issue that has been discussed for long. Yet, I cannot find the answer eventhough I used the whole afternoon to read the forum and other sites.

Actually, I am using Job Queue to auto load some reports to a specific folder on the DB server. I used Codeunit to do so and everything is fine as if I execute it manually.

However, when I place the codeunit to Job Queue, I observe that Excel has been successfully executed in task manager, seems data loading is also fine. But, the final stage of SaveAs stucks and finally Job Queue Entry Log says "SaveAs method of workbook class failed".

Honestly I did not expected such problem and my schedule of submission is very near, could anyone knows the solution please kindly tell me?!!!!

Thanks a lot in advance!

Louisa