The following users could not be activated

I have a user that when clicking the activation link in the email gets the error message “Could not create user” and when I try and manually activate them through unconfirmed it gives me the error message of “The following users could not be activated: “.* .

I’m using a multisite setup and WordPress did create his account, but it won’t activate it.

I doubt its an issue with unconfirmed, but I was hoping someone might have some insight into what was going on.