Even though This topic is 2 years old I still found it extremely helpful! I recently moved from the UK to HongKong, of course I needed my GW2 fix and could not log on as I was on a different network and needed to re-verify. I tried and tried and tried, I have my authentication but to no avail, I have been frantically searching the forums for anything to explain why my correct info was not working and here it was all along, a tiny 1min time discrepancy. THANK YOU! I was starting to rip my hair out.