Group issue

[Michael Sullivan]

I'm running RH9 on my main computer.  I am the root user and there are
two personal accounts on it.  Yesterday I tried to change the two
personal accounts so that they would be in the same group - the users
group.  The next time I tried to log into my personal account, it gave
me the message "The system administrator has disabled your account. 
What did I do wrong, and is there any particular file I need to delete
to get past this save deleting all the . hidden files and folders?  I
created a new directory and copied the files into it and deleted and
reissued the accounts, but if this happens again, what should I do?

-Michael Sullivan-