Roberto-
Yes, I did see that but, that isn't really my problem. The whole system doesn't crash and they don't get that error message mentioned in the KB. It is only the one user that gets kicked out of Nav and he gets no error message.
I logged into their Remote Desktop with an admin login. Went into Nav and I have no issue with choosing columns. I got out of Nav and then did shift-right click on the icon and logged in as that user. When I try to do Choose Column, I get kicked out of Nav. It seems like permissions to me but I don't see anything odd about his permissions
Thanks