You want to make sure your watch folder has the correct permissions. I’m on a mac, but in case you’re on a PC there must be a similar process.
On a mac:
go to the watch folder and het CMD+i to open the info box. at the bottom, in the ‘sharing and permissions’ section, make sure you have read/write enabled for all computers in the network.
That should do it 🙂
I think it might also be the case that if your watch folder is inside another folder(s), the parent must also have read/write enabled. But don’t quote me on that.
Hope this helps 🙂