Make sure you're using your correct username and password. Remember the password is case-sensisitive. If you have trouble remembering your password or username, contact support and we can send you your access information (only to the alternate email address set in your Control Panel settings - so make sure that's a current working email address.
Make sure you're trying to log in to the server on which you have an account. If you signed up for a USA-hosted account, you won't be able to log in on the Netherlands servers. The USA servers are at neomailbox.com and the Netherlands ones at neomailbox.net or neomailbox.nl.
Just send us a mail if you can receive mail but cannot send mail or access the Control Panel, and we'll re-activate your account and increase your limits if necessary.
Generally, as long as you're sending legitimate mail and not spam or unsolicited commercial mail, we'll be happy to raise your sending recipient limits to whatever works for you. Contact This e-mail address is being protected from spambots. You need JavaScript enabled to view it to get your limits raised.
If you expect to be sending mail in larger quantities than the default limits for new accounts allow, it's a good idea to let us know beforehand and have your limits raised. That will prevent your account from being disabled if you go over the default limit.