The page you are viewing is not a valid endnote Web registration page

There is a Endnote X8 version in my Win 10 computer.

However, when I try to use the Sync function, it seems it doesn’t work and  a pop-up message appears every 5 mins (Please see the attached image), which says that:“The page you are viewing is not a valid endnote Web registration page…”

Anyone know how can I solve this problem? Thanks.

Please contact Technical Support directly

1-800-336-4474 option 4 then 1 or

https://support.clarivate.com/Endnote/s/technicalsupport?language=en_US