Mail Function Problem

Hi All, I have problem with mail function. Mail function is correct working while i send mail to any domain specific mail like
But when i send mail to any other account of google, yahoo or others then it is not send like
Kindly help me at this matter because before some time all working fine but suddenly all are work stopped only
Please help me this is very urgent

Hi @neerajkumar,

What version and what software are you using?

Alec Smecher
Public Knowledge Project Team