When using local switching access points in combination with web-portal authentication, the following error messages appear in the system logs and seemingly random users can not access the web authentication interface:
TUNNEL_LIMIT_REACHED AP 71 is at tunnel limit
TUN_REMOTE_FAILED Cannot set up tunnel remote=10.10.8.127 orig_vlan=3596 remote failure: TOO_MANY
There is a known issue with MSS 7.6.3.1 causing this tunnel issue. The issue has been addressed in MSS 7.7 MR3.