Mail Fetching Keeps Stopping

Mail Fetching Keeps Stopping

I realised that emails were not being recieved and after checking I noticed that mail fecthing had stopped.
When I start it again it immediately stops and creates an error in the system log message as below:

System Log details :
System Log Message :
Module : MAIL_FETCHING
Sub Module : -
Type : Error
Action :
Occurred At : 08/12/2015 10:05 AM
Probable Cause :
Performed By : SYSTEM

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