Should your DNS settings change, it’s possible your network may become inaccessible or be caught in a redirect loop. You will need to update your settings with your registrar, but you can access your Domain Mapping page at the following URL:
http://networkname.ning.com/main/admin/editDomainMapping
You will need to switch out networkname with your network’s subdomain. After entering that URL in your browser’s address bar, sign in as the Network Creator, and enter the URL again (if necessary). Clear out the existing Alernate Domain, if one exists, switch back to the Default Domain, then click “Save.” It can take a few minutes for the changes to take effect, but this should restore access to your network on the default Ning URL until you can update your DNS settings.
If you’ve made those changes, but the network still won’t load, try adding “/?text” after the URL, wheretext can be any random string (eg: http://networkname.ning.com/?asdf123). This forces your browser to pull a fresh copy of the page.