Dave T wrote:If it is installed in the default location all you need to do is give fs9 folder full access .
1.Right click on Flight Simulator9 folder
2.Properties from drop down menu
3.click on security tab
4.click on edit
5.highlight the user(computer name)
6 check all boxes giving fs9 full control and click ok
and then right click on fs9 folder and uncheck read only click apply and when its doneclick ok. I run both FS9/FSX on W7 64bit without any UAC problems in the default location.
This is one way to get around the permissions problems that started with Windows 7 and it will and does work with no problems.
But for me I like the old keep it simple approach all you have to do is not to install FSX or FS9 in the default location and than you do not have to go through all of the other stuff.
As you can see by my signature I am using Windows 10 and have no issues with FSX or FS9. Your problem could very well have to do with the Three screens that you use. What device do you use to get the three screens. I would bet that a update changed something to where the device no longer works the way it did. I would suggest you look for a updated driver for the device that just might solve your problems.
If the Video card you are using is made by NVIDEA or uses a Gforce GPU than there is a program called GFORCE EXPERIENCE here is the link
http://www.geforce.com/geforce-experience/downloadThis program will keep your video card driver up to date. It will automatically uninstall the old driver and install the new driver without you having to do any thing.
It really makes updating your video card driver a simple task.
The only thing you have to watch out for is if you use the default install it will install a 3D driver and since i do not have a 3D display I chose the custom install and do not install the 3D driver