Plesk is only allowing me to create one mailbox. I have tried everything to create additional mailboxes and nothing seems to work. Any ideas?

Thanks,
QuiK

what is the error your getting? what happens?

The only time I've seen that is when the domain was created to only allow for a single mailbox. In Plesk go to the domain and then the Limits icon to see what it's set for.

If you can't change it there for some reason, you may also need to check the Limits of that particular Client, as you can limit how many mailboxes each client can set up too.