3.5 to 7.0 workbook conversion issue

Hi all,

We are using BEx 3.5 as our frontend. we are trying to convert only the workbooks from 3.5 to 7.0. but while doing this it gives out error saying "A critical program error has occured. The program will now terminate. Please refer to the trace for furthur information".

for some of the workbooks it converts without bring any data where as the data exists.we are using 2007 excel.

Can anyone suggest me the reason after that. Your help will be appreciate.

Thanks

Diksha.