Unable to connect to SAP BW server Incomplete logon data

Hi, experts, I have a question regarding query data in BW from a Webi report.

I have two users in my BOE XI 3.1 SP3. The first user (ZTONY) is imported from SAP BW. When I use ZTONY to login InfoView via SAP authentication, I can read a Webi report that contained data specified for this user (i.e. I can read only 2 companies' sales data instead of total 10 companies') - which means the option "Use Single Sign On when refreshing reports at view time" in Universe Designer has been tested successfully.

Meanwhile, I have another user (TONY) created in BOE directly with Enterprise authentication. I also assigned ZTONY as an alias of TONY. (Does that mean now the two users are the same except for the authentication method? )

However, when I user TONY to query same Webi report as described above, I can't refresh the report and get an error says "Unable to connect to SAP BW server Incomplete logon data" - I feel SAP BW doesn't recognize TONY as the person with ZTONY. Is that correct?

Is there any work around that TONY get the same previlige in SAP BW as ZTONY does (of course, in BOE)?

Thank you!

Tony