Can't run Microsoft's Flight Simuilator 9 on Windows 8.1

It has been suggested that the trouble I'm experiencing is due to having reinstalled Windows 8.1 to get rid of unwanted software installed by the PC's manufacturer (HP) and not clearing the BIOS.

I trust that it doesn't infringe any protocol of this forum (I can't see that it does from the rules) if I give a link to the postings on the forum where I have explained the steps so far.

If anyone can offer further help I would appreciate it.

The thread is here FS2004 on Windows 8.1 (again).

Just a little suggestion: Provide us with some insight to the specificity of your personal case.

Some examples (or at least what I would have done):

• Try starting FS9.EXE (or whatever the shortcut on your desktop is) with admin rights (right click and 'start with admin...')
• Use snipping tool to take a snap shot of the error dialog that appears when FS9 crashes / fails to start (TBH I would have typed in this to google as it has most likely already been addressed as FS9/FSX is extremely popular in the flight sim community)
• Provide a copy of the crash log as coping the relevant information (if it is not a hundred pages long) or upload the file to the cloud and sharing the link here
• Use Window's compatibility feature to emulate or whatever the heck it does to make windows more friendly to older versions of windows (which your product was designed for) i.e. FS9 <=> FS2004 A Century of Flight (same thing, diff name). Windows XP was released so first I would have tried SP3, then decrement the SP till you are just at Windows XP

Honeslty Brah you need to give us more than that. You should also include all you specs. Here's mine:
Win 8.1 Pro w/ MC x64
i7-2600k @ 3.4 GHz
14 GB DDR3
4GB Nvidia GeForce GTX 670 FTW
1GB ATI Radeon HD 6870

it all helps but along with specs we really need what it says when it crashes or won't start. I am installing FS9/FS2004 right now on my machine so I'll let you know, but I'm sure it will work.
Simple search (and I mean little to no effort) will produce something viable to answer your general question as to it working on 8 or not. "will fs9 work on windows 8.1" -> Trying to install FS2004 on Windows 8.1...

I read that the first 4 posts in the thread and it reminded me of UAC (run as administrator / with admin rights) and I was like, oh ya,,, i'm a dumb rubbish! This is usually the #1 solution to all your problems.. ALWAYS TRY THIS FIRST (BUT KNOW AND TRUST YOUR PROGRAM AND WHERE YOU GOT IT FROM) elevating a icon-less .exe that you don't know what or where it came from is more than stupid homer simpson street cred and is just asking for a nice F bomb to discombobulate your PC.

I will still install it just to check for you but I'm 99.99% sure it will work, we just need to figure out if it's you or your computer. I will edit this when I have some info for you.

Hairy, is there a way to run programs not in Admin mode??

some of my programs appear to force open or "need" to be opened in Admin mode.. but I just want to open them in "standard mode" not with Administrative privileges.

like so:

It's not due to the Microsoft update which stops old SecuROM & Safedisc games from launching is it.

http://www.eightforums.com/gaming/72742-m-s-flight-sim-9-suddenly-requires-privileges.html