That is a OS owned special directory that you cannot sync to as a normal user (and in theory you should not). You can try changing the permissions of the folder (bad idea) or running syncthing as admin (bad idea). Ideally you’d sync in to a normal directory instead.
Yes but it is a sub folder of program files of course in need to sync, not the whole folder, and the thing is i already do this on 3 other PC.
On this particular PC i can’t…
Just curious: Do you need this for Software deployment? Or are there regular config updates to be necessary in that folder? If it’s a domain, Software deployment should be more easy by making a custom WIX MSI package and let this set config dir perms automatically along where required. I’m doing this if nothing else fits and let Syncthing do the rest (config only).