LDAP server - WiFi authentication issue on FortiAuthenticator

[alladas]

We recently had a Firmware upgrade to the FortiAuthenticator (v5.1.0). Our wireless AP users are authenticated via FortiAuthenticator anytime. It worked fine until we had this upgrade and after the upgrade few of our Windows 10 machine users are having the authentication issues. 

We had username authentication from our AD but some for some reason, the logs shows that the "host" name not found and rejected. The host name showing in the logs is the computer name but not the user name. We never mentioned the authentication by computer name. 

Can someone help me resolve these issues?

Inputs appreciated in advance.

[cbabfat]

There is already a 5.1.1 patch.  You may  want to try that.  Otherwise, I would roll back to 5.0.0 or earlier.  Whatever you upgraded from and have backup files for.  There are too many bugs in 5.x.

Chris

[alladas]

I doubt it's some issue with the Windows 10 OS. It works fine for all other Windows versions and Mac's. 

Also, have you any clue why the authenticator taking in both the username and computer name based authentication? We set authentication only for username. This is been observed even before upgrading our firmware.