Hi giulianocardoso,

I think that SSRS 2000,2005 and 2008 reports all use different versions of the Report Definition Language.

Whilst Visual Studio 2008 \ BIDS 2008 will happily upgrade reports written in RDL 2005 (or even RDL 2000 for that matter) to RDL 2008, I do not believe that there is any downgrade type functionality to convert an RDL 2008 report to an RDL 2005 or RDL 2000 format.

Unfortunately I think that you need to recreate your reports from scratch within VS2005 or BIDS2005 in order to make them compatible with SSRS 2005.