When i am trying to save the "Main Settings" Page under admin panel, it throws following error

Error 400: Bad Request
Your browser sent a request that this server could not understand.

Probable reasons are:

    * You sent a plain HTTP request to an SSL-enabled server port. Instead please use the HTTPS protocol to access this URL, like this: https://example.com:8443/
    * You made a typo in the request, e.g., typed a comma instead of a colon. Please re-check the URL.

Please contact your webmaster if you are not sure what goes wrong.