Error with login

Hi everyone.

When I log in to my webpage, having typed username and pass and submitting i get an error from explorer saying

Internet explorer can not display the webpage
You are not connected to the Internet
The website is encountering problems.
There might be a typing error in the address.
Internet connectivity has been lost.
The website is temporarily unavailable.
The Domain Name Server (DNS) is not reachable.
The Domain Name Server (DNS) does not have a listing for the website’s domain.
If this is an HTTPS (secure) address, click Tools, click Internet Options, click Advanced, and check to be sure the SSL and TLS protocols are enabled under the security section.

i then have to type in the address of my page to the address bar in order to enter my page. However I’m then logged into my site and can enter the admin dashboard

Does anyone know why this happens and how i can solve the problem?