I need to be able to send messages!

eM will not send the messages in my outbox; however I can send messages. I can also send messages from my eM client on my laptop. The error message I get tells me to check my settings however I have not changed anything. What could be wrong? Any help would be greatly appreciated!

To clarify since I made a mistake. I can receive messages however I cannot send them from my desktop. I can send and receive from my laptop.

Are you using any anti-virus or a firewall?

I am but that was not the problem. Comcast decided to block Port 25 without telling anyone and so I could receive but not send. I switched to 26 and all is well. Thank you for the response.