Hi Stephen,
We didn't actually move server, we just upgraded our virtual server, but it creates a different machine guid, I wondered if that had something to do with it, but that was a few months back now.
Today it has began to work again, I'm pretty sure it's a cache problem, however it also didn't work in chrome incognito, but today it's working for all of our staff in all browsers again.
It was strange that it happened while we were all on annual leave for 2 weeks, but all good again!
Great product, makes supporting users a hell of a lot easier!
Thanks again :-)