Windchill : Principal already exists error

Dear All,

I am facing this issue in Windchill 8.0. I've checked this errorin Google too and could'nt find any relevant information. Pls help.

In Windchill 8.0 , for an exisitng project of ours , when I try adding new users , I receive an error message saying " principal already exists : <employee_email>".

* We receive error saying "principal adready exists, along with our user email address, who is not part of that project anymore.".

please suggest. This error is preventing us addign new users.