Over the last several days my organizations has been experiencing intermittent  issue with logging into Salesforce. Access issue appear across a number of browsers including IE9, Firefox 29 and Chrome 36. For our organization we use a custom url to access Salesforce and when attempting to sign in via the url the page often displays a message regarding a problem with a redirection issue. While we do use a single sign on (SAML) with the custom url, other services that make use of the single sign are all working, and there are even times when the single sign on for Salesforce is working properly. The problem is most consistent with IE9 in that upon attempting to access the page it returns a simple page cannot be displayed, within firefox the message offers the following, the page isn't redirecting properly, firefox has detected that the server is redirecting requests for this address in a way that will never complete. This problem can sometimes be caused by disabling or refusing to accept cookies., and lastly the results for  chrome are this page has a redirect loop.
Support via cases with Salesforce has been extremely disappointing as they continue to reclassify my case and close the call, so I am reaching out to see if others have had the issue and might offer some advice.