I think it is unlikely that a Windows update has caused your problem (although I'm not sure what might be causing your problem).
First of all, please try clearing your browser caches before reloading your gallery's web page to see if this makes a difference.
Also, if you have any browsers extensions installed, please try temporarily disabling them to see if this helps.
If you still cannot view your gallery in certain browsers, then please post a link to your gallery's web page so that I can take a look at the problem for myself. (You should be able to view your gallery in all major modern browsers: Chrome, Edge, Firefox, IE8+, Opera, Safari.)
Once I'm able to see your gallery, I should hopefully be able to determine the cause of your problem and propose a solution.