At datasource page , you should see the SQLServer JDBC driver record
already there TOO
Change the driver file name : sqljdbc.jar -> sqljdbc4.jar
On the other hand , you can copy rename the driver to sqljdbc.jar first , it’s all up to you.
Now , you should got the successful string without change user/password. (if something error popup , restart the WASv855 and let the driver load in memory )
Being here , we had already migrated the original profile from WASv7 to WASv8.
Begin to reinstall wizbank EAR with familiar steps you already know