If business needs don't allow the use of Active Directory uid attribute and demands sAMAccountName to be used instead, WebSphere Portal v8.5
we should do the following changes.
1) Create a backup for your winconfig.xml file;
2) Open the winconfig.xml file up with a text editor that will not add any special character to it.
3) Change the following line from:
and also add, the following line
Restart WebSphere Portal server or WAS server.