Salesforce | System.Callout Exception: Unauthorized End Point

I tried to send REST request to my server on click of a custom button in Salesforce. It shows me “unauthorized end point exception”.

Solution : To resolve this issue we need to add the server address as a remote site in Salesforce. Here are the steps to add remote site.

1.  Go to Setup->Security Controls:

2.  Go to Security Controls->Remote Site Setting:

Here create new remote site setting for server address then it will work fine.