Not too sure about any risks involved as yet. I've installed, over the years, FS9, FSX, P3D on my laptops, the 20 odd PC's at our VA, the 2x sims we have built up at our VA, a Tomahawk sim at another VA that also has 6x PC's running FS2004, using a bunch of various control cards, payware & freeware planes & scenery & on Windows 7, 8, 8.1 & 10 all with UAC turned down. Never a problem at any stage. Some, not all, running as Admin.

 

It's quite interesting, as well,  that guys are saying not to touch the UAC, (which is all about  Microsoft complaining, & stopping any changes), & I'm sure that most of these guys are also complaining about the auto updates in Windows 10 doing it's own thing. Same thing. If the program/add-on wants to go somewhere, that's where it's gonna go.

In the early days (very), when I did have a separate install, some of the installers auto installed into a non existant folder where it thought FS should be. That was a pain trying to sort out.

 

BTW, Remember, UAC first arrived with Windows Vista!! & we all know what a lemon that was.. So, turning it off & running as Admin, takes us back to the same ' Security' constraints, shall we call it, as Windows XP. & we all loved XP (at the time) & there were no issues then.

 

Anyhow, When I do ever have an issue, it has been about 10 years without one, I will post my apologies, cap in hand, to all.

Starting in Win 7 (as published in PC Magazine) turning UAC down affects the user level privileges. Program level accesses were added in Win 7 as far as applications accessing anything in the Program Files  heirarchy. Later apps had code to elevate their access privileges. Older ones as in the product in my tag needed both privileges set in thir properties.

 

Win 7 HP and Win 7 Pro (OEM) have different access level properties windows. HP has two easy dialogues, one in the first window and then another in a second Advanced window, each with Run Admin Choices. In Win 7 it gets more complicated in a second dialog series.

 

(I went from XP to Win 7.)

 

To avoid messy privilege issues that's why a lot of developers recommend not installing FS in the default Program Files tree.

 

FSUIPC was updated to raise its privileges but then due to a complication with its signature vendor it had to remove its signature check (Verisign or whover) to run in Win 7's enhanced security.

So, very basically, for the layman, in simple terms, by running with UAC turned down & as Admin, I do not get nagged by any program or OS & I have full access to editing & to whatever I want to do. For any malicious activity, I have, as everyone should have, my firewall, anti virus & anti malware programs to look after things. & software gets installed where they should be.

FSUIPC? Great, has always worked for me. Best add-on ever.

 

BUT, I'm only giving my experience over the last 10 years. I do not want to be limited at all. I'm no expert, but It works for me. (freeware, payware, editing, et al)