Avoiding Log-In Screen

Hi all,

our system is set up for SSO. Once you logged on to the network, there no other logon necessary for any SAP system. But we are facing one issue.

Our users run BW webqueries from R/3 (by clicking a link) within a R/3 transaction (with the html viewer). For the first time, when they run such a query, a log in screen appears to log in to BW. How can we avoid this popup?. Does anybody know what to do? Any help welcome.

regards

Siggi