SMTP server services switched off.

[onestop]

How can I switch on this service.
When I click on the restart the page keeps on loading and comes back to the old page.Please suggest.

 

[Satoriya]

Please, review these acticles where common reasons of such issue are described:
http://kb.odin.com/en/1387
http://kb.odin.com/en/3954
Hope, they will be suitable for your case as well.