Server unavailable error.

One of the most common problems you face whenever you log into AX is "Server unavailable. Check your configuration and Network connection and try again"

 This is because the ax service has stopped. Just start the service once again and AX will work fine.

 Once more which you see is Application Object Server is unavailable.  This is either your server is shut down or server has stopped.

Explanation :
                AX is basically a domain based software. There will be a common server to all the client machines. So once your client machine is installed with AX, next you have to configure it to particular server. To do that, run Microsoft Dynamics AX 2012 configuration, Connection Tab and Add button, enter the server name, TCP/IP port number and configure it to the server. You can also create your configuration or Add configuration file from Manage button. click apply and the your client machine will work fine.