"You are unable to log in to the user account [account name] at this time.

Problem:  an AD bound Mac shakes off login attempts and returns a message that says:

"You are unable to log in to the user account [account name] at this time.  Logging in to the account failed because an error occurred."

There are two things to to try:

First, update the Automounter master map as outlined in this Apple KB article:

http://support.apple.com/kb/TS3346

Secondly, if the user has a home folder path specified in their AD profile (Profile tab), remove it.

Shaky login on Mac

Normally shaky logins are caused by missing or corrupt edu.mit.kerberos files so always check that first but you might also want to look at the user's e-mail address in AD too.

We had a user who couldn’t log into any bound Mac using his AD account however he could log into a PC. On the Macs, he would get a shaky login box and a cryptic error saying “you can’t log in at this time”.

Checking his AD account I noticed that he didn’t have a secondary SMTP of @corp.ipgnetwork.com. I added the SMTP, waited for replication and then he was able to log in.