Will switching FS2004 from Windows XP mode to Vista mode break my setup (FSDT scenery)?

Rich,

You’re thinking about it the right way—changing the Compatibility mode can change how FS9 (and installers) behave, but it usually doesn’t “break” an already-working setup by itself. The bigger risk is simply permissions/UAC and where FS9 is installed, not the Vista checkbox alone.

A few key points about Compatibility modes

• Compatibility mode is applied per EXE (and/or installer), not “the whole sim” in some permanent way. You can run the installer one way and FS9 itself another way.
• Switching FS9.exe from XP mode to Vista mode typically won’t damage scenery entries or aircraft installs. Worst case, you’ll see odd behavior with modules that hook into FS9 (gauges, DLLs) or file writes if Windows starts redirecting things due to permissions.
• A lot of “doesn’t support XP” language from scenery vendors is really about the installer/runtime requirements (SimConnect, .NET, C++ runtimes, Addon Manager/Couatl, etc.). That’s a bigger factor than the compatibility dropdown.

What I would do (safe approach)

1. Don’t change anything yet. First, back up your FS9 folder and your FS9.cfg (so you can unwind quickly if anything gets weird).
2. Run the FSDT scenery installer in Vista compatibility mode (right-click the installer EXE -> Properties -> Compatibility -> Vista), and also tick “Run as administrator” for the installer.
3. Leave FS9.exe in whatever mode it’s currently happiest in (XP mode, from what you said), at least initially.
4. After install, start FS9 normally and verify:
   • Scenery Library entries are present (and not duplicated).
   • No missing texture/object messages.
   • No CTD on startup or when loading the airport.
5. Only if the scenery clearly requires FS9.exe itself to be in Vista mode (you’ll know quickly), then test flipping FS9.exe to Vista mode. If you see new issues, flip it right back.

About “Will it definitely work in Vista?”
I wouldn’t trust an AI answer on this one. FSDT “supports Vista” doesn’t automatically mean it will behave perfectly in every modern Windows environment running FS9, because the usual stumbling blocks are:

• Installer prerequisites/runtimes
• Permissions (especially if FS9 lives under Program Files / Program Files (x86))
• Older modules that expect a certain Windows behavior

So: it might work fine, but I’d treat it as a test-and-verify rather than a guarantee.

Quick questions so I can give you a tighter answer

• Where is FS2004 installed on the new PC? (Exact path helps—e.g. under Program Files (x86) or a custom folder like C:\FS9)
• Which specific FSDT airport(s) are you trying to reinstall?
• When you say “doesn’t support Windows XP so I can’t reinstall,” what exactly happens—installer refuses to run, errors out, or installs but scenery doesn’t show?