Export standard report in Excel format doesn't work

Hello,

we have a client using RTC 4.0.2 and needs to export a standard report "Open vs. closed WI" into Excel format.

Steps:
Web Browser/Reports/Shared Reports.
Choose the report and open it. Press Export and choose Excel format.


I have used MicrosoftExcel 2010 and before it opens the files exported I got the error message: "The file you are trying to open,  "report-5.xls' is in a different format than specified by the file extension. Verify that the file is not corupted and is from a trusted source before opening the file., Do you want to open the file?"
Choosing option Yes I got the file opened in Excel but without any data but the table header.
I mention, I can see the report in Dashboard (added as a widget) and it looks ok there.

Exporting in OpenOfice, I don't get the error message but after export I don't get the content of the table either. Only the table header

I have tried this operation also for another RTC project (4.0.7) and gotten the same error.

Do I understood the way in which the export is thought completely wrong or is any other explanation?

Can anybody help on this issue?

Thank you,
Zica