Windows Authentication Required Window Started to Show Up

We were having an issue where we could not log into SDP because of recent changes made to Firefox. Did some digging and located a fix in the forum that added a ciphers line to the server.xml file. This fixed the problem. I upgraded to SDP 9.1 and now we are having an issue where every time we try to log into SDP we get the Windows Authentication Required window pop up. Clicking Cancel brings us to the ADP login page. Does anyone have any idea why this is happening and how we can fix this? We do have to use our badges to log into our computers at work. It doesn't bother me but our user community are opening tickets because of this and we have been asked to fix it. Any help would be greatly appreciated.

Thanks