Hello everyone, finally the support could help me and we fixed the problem. At least I do not fully understand which of the several executed steps is the solution, but I can tell you what probably could help: Update every involved components (Windows, Kaspersky, Browser) Use the restore settings function of Kaspersky After every change you do always restart your computer At least everything I did to fix that problem seems not to be working. But after several restarts of my system it finally worked again after I executed all steps the support told me to. Don’t hesitate to contact the support members. They are really fast and good in the work they do!