When creating a report in Admanager Plus with attributes containg dates I get the following error message:

"Excel found unreadable content in Report.do. Do you want to recover the contents of this workbook"

When I recover, the message  "Repaired Records: Cell information from /xl/worksheets/sheet1.xml part" pops up.

I get this error in "Recently created Users" for an example.

Is this a known issue? 

Regards Thomas