First close all Avanquest software and download the
following patch from this link here.
Double click on the patch to run it, then message will appears in French stating that no errors are found, click on OK to close.
Then click using the right-hand-side mouse button on top of WebEasy shortcut icon on the desktop and select option Run as Administrator (if such option is not present press Properties then select option Compatibility and tick box in section Privilege Level, then save and close with OK). This should help the program to start normally.
Please submit ticket stating the exact licence number, if you keep experiencing difficulties running the software.