Strange Login Redirects

On first accessing the admin dashboard I get a redirect...

Gateway Timeout

The gateway did not receive a timely response from the upstream server or application.


On second try I get this which takes me to the login page.

Same problem in ff, chrome and ie.

I am able to login on my phone (two different browsers) and my other sites are ok. I ran my antivirus but it did not pick up anything.

I no longer get the Gateway timeout but the second link get me to the login but to be safe I did not login.

All I've been doing is security and all important wpmu updates. I've not changed anything at all since the problem. Yesterday I was able to login. Just this morning I got this problem.