Can't send any emails out

Question

Hi there,

     I've got a hotmail account & it was working perfect up until a couple of days ago. Then when i tried to send a few emails out i just got a message from postmaster saying email failed to send. I've checked the addresses that i was sending to were typed correctly. I tried adding an alias to Outlook.com. Nothing's worked. I'm not very technical so can anyone help me at all with this, but in plain english. Technical terms confuse me.

 

Nita