i have a client that wants to conect at the same time with his iphone and outlook but he cant do both at the same time i cant find an option on the mail enabler that can give permitions to allow two sesions at the same time is there something we can do on the mailenabler to make this account do that?

When your client tries to use both, take a look at the log file. Does it provide any helpful errors?

there are no errors when hes iphone is active he canot log in using outlook or any other program it just keeps telling to put the log and pass, but when he turns off his iphone then he can log in fine

I've seen this error when you're using POP. POP doesn't support multiple connections in anyway that resembles efficiency.

I've never seen it if they're using IMAP. With an Iphone, IMAP is the way to go.
-s

It does indeed sound like an odd one - what software is your server running for IMAP / POP ?

Also do you have a limit enabled that limits per IP connections ? (If he's testing with his IPhone on Wifi it'd probably come from the same IP)

As ElfinStrider said, it's a limitation of POP3. The behavior is by design.

When you connect, the server keeps the index of what mail you've downloaded and which mail is new. Multiple connections cause a file locking issue.

You'll have some of the same problems with IMAP under certain control panels, but Dovecot handles it well.