BI-Portal integration problem

Hi Experts,

I've done the steps in Integrating BI and Portals. I've come across an issue where i initially setup a system as the BI mastersystem and then deleted the system and reassigned it to another system. I have alias SAP_BW on this new system as well. however when i run a query from query designer it still looks for the old system. Then as per note 919197 i removed all duplicate mastersystems and restarted. but i still have the same issue as BEx is still looking for the old master system. I get the error "child not found" and "Error while reading aliases" .

Could anybody please tell me how to sort this issue out.

thanks and regards

dilanke