3822425 - Why am I getting a message the email address is invalid while creating a new user manually or through imports?

When I tried to create a new user,manually or when I send an employee import file to create users, I get a message: The e-mail address '12345@xyz ' for employee ID 'abc' is not a valid address.

When creating a new user manually or through employee import, a warning message comes up that the email address is invalid. , KBA , CON-CA-ADM , Administration , Problem