Only certain users cannot log on to storefront.

Following events can be seen on the storefront server :

Security events logs :
Event 4625, Microsoft Window security auditing
Failure Information :
Failure Reason :  User not allowed to logon at this computer.
Status : 0xC000006E

Citrix Delivery Service event logs :
Event 1, Citrix Domain Service
FailedWrongWorkstation

If the users are logging in via Citrix Gateway, we might see below error:

Windows error code 1329 translates to, ‘This user isn’t allowed to sign in to this computer’.

Open on Citrix.com