Above is my problem. The preference "Open Documents as Tabs" won't stay unchecked. Sometimes it won't revert for several days, other times it will revert every time a new document opens. Lately the later has been the general case. Has been a problem for some time for me. Across several years with Windows 7, 8, 8.1, and now on a new machine with Windows 10. I have a multi monitor set up and need the files to open on a second monitor. Doesn't seem to matter which of three monitors I designate as my default main monitor in Windows. This is a personal machine on a private network and I'm the only administrator. Any thoughts?
Current Desktop I7 6900
128 gbs RAM
Monitors are NECs
Do all your other preferences stick? Just this one doesn't?
Yes, that's correct, only the tabs reverts to default.
Just thought it might be a general permissions problem. It's been seen before.
After working with two or three monitors for years, where I routinely did what you describe without problems, I've now returned to single monitor setups. So I can't test any of this.