Error When Exporting To Excel Using SSRS 2003

Hi,

I have encountered an error when attempt to open a report which is exported to Excel using SSRS2003. It looks like this:

Microsoft Office Excel File Repair Log

Errors were detected in file 'C:Documents and SettingsTocsonEIMy DocumentsRigidReports
ptRigidTransactionSummaryReport3.xls'
The following is a list of repairs:

Damage to the file was so extensive that repairs were not possible. Excel attempted to recover your formulas and values, but some data may have been lost or corrupted.


At first I thought it was because of the sheer bulk of the report since when I break down a month's report to every 5 days, it would export without error. So I thought that if I can break a whole report into several worksheets using page break, it might work. Unfortunately, although I did succeed in exporting the whole report into several worksheets, I still encounter the same error. Now I have no idea on what the root of the error is. Note that the same report can be exported in other formats and can be opened without error. Except for a case when I tried opening the same report exported in XML using Excel, an error which might be related to the error above occurs which says that there's an invalid unicode character in the xml file.

Any help in determining the root of the problem and a solution to it?