[rt-users] * User could not be created: Email address in use

[Rainer Sigl]

HI,
on my rt 2.0.14 I let the user create a ticket with his email address. The
ticket ist already resolved and now I want make a userid for this person
as a stuff member. Then I get the error message "     * User could not be 
created: Email address in use"
Has anybody an idea solve the problem?
Regars
Rainer