We use a program which runs in the notification area, its icon sitting there for as long as it runs, a bit like Dropbox does:
PROBLEM: On thousands on computer it shows fine, but on two particular computers, it does not appear anymore.
It used to work on these two computers too. It still displays correctly on thousands of other computers. The only unusual thing that the two computers seem to have in common is that an app called "FreeFileSync" is installed.
The icon is not listed at "Control Panel > Notification Area Icons" either. The program is running correctly, as attested by the Windows Task Manager and the program's log file. Reinstalling does not help. The computer is configured to always show all icons:
QUESTION: How to fix this and have the icon appear like before?