This is a very weird problem. I made a connection to the SQL server using Sharepoint Designer. However when trying to give "All Authenticated Users" access to that database from BDC. When I click to "add" the "All Authenticated Users" nothing happens. The option I chose does not get added. As if the "Add" button is not responsive. Any ideas what could be causing it?
Note that I'm able to add users to other pages such as "farm administrators" and "site permissions" but not to the BDC.