Vijeo Citect Historian Web Client is not supported on window 8.1 or window server 2012 operation systems.

Hi Shing Hin 

Downgrading your OS, while it might temporarily get around that problem, at some point you going to need to upgrade the OS and also Windows 7 is End of Life as of 2020.

Given Citect Historian is no longer being actively developed, this might be a good time to migrate to AVEVA Historian. Until 31 December 2021 significant discounts are being offered for customers to Migrate from Citect Historian to AVEVA Historian. You can contact your local Schneider Office for more info about licenses and migrating your history as well.

Hi Richard J 

Thanks for your suggestion , the EOL of Window 7 is my concern also . AVEVA historian may be the best choice of this situation.

Hi Richard J 

Thanks for your suggestion , the EOL of Window 7 is my concern also . AVEVA historian may be the best choice of this situation.