Where is the FS9.cfg file in FS2004 on modern Windows?

On Windows 10 and 11, Microsoft Flight Simulator 2004 (FS2004 or FS9) stores FS9.cfg at %APPDATA%\Microsoft\FS9\FS9.cfg. Press Windows key + R, enter %APPDATA%\Microsoft\FS9, and press Enter. It is a per-user file in hidden AppData, even if FS2004 itself is installed on another drive.

How do I open FS9.cfg on Windows 10 or 11?

The quickest method is to open the FS9 folder directly through the Windows Run box, which avoids having to reveal hidden AppData folders.

1. Close FS2004 completely. Changes made while the simulator is running can be overwritten when it exits.
2. Press Windows key + R to open Run.
3. Enter %APPDATA%\Microsoft\FS9 and press Enter.
4. Locate FS9.cfg. If Windows hides known extensions, the file may appear simply as FS9.
5. Make a backup before changing or replacing it. Copy the file somewhere safe or create a clearly named backup such as FS9.cfg.backup.

Use File Explorer’s View or Show options to enable File name extensions. This helps prevent accidental names such as FS9.cfg.txt, which FS2004 will not treat as its configuration file.

Where is the full FS9.cfg path?

The full path is normally C:\Users\your-user-name\AppData\Roaming\Microsoft\FS9\FS9.cfg. Using %APPDATA% is safer because Windows expands it to the Roaming AppData folder for the signed-in user.

A mistake we see constantly is searching beside fs9.exe. Installing the simulator on another drive changes its program location but not this per-user AppData path. Our guide to the FS2004 installation folder and VirtualStore explains how those locations differ.

Each Windows account can have its own FS9.cfg. Older instructions written for Windows XP may instead mention Documents and Settings and Application Data; on Windows 10 or 11, use the %APPDATA% path above.

Why can’t I find FS9.cfg?

A missing FS9.cfg usually means FS2004 has not created it yet, Windows is hiding its extension, or you are looking under the wrong Windows account.

• FS2004 has never completed a normal start: Let it reach its main screen, then close it normally so it can save its configuration.
• The extension is hidden: A file displayed as FS9 may already be FS9.cfg.
• You opened the installation directory: The normal configuration file is under Roaming AppData, not beside fs9.exe.
• You used another Windows account: Open %APPDATA% while signed in as the same account that runs FS2004.
• The filename is wrong: A manually created FS9.cfg.txt or empty text file will not replace the genuine configuration.

FS9.cfg sigue sin salirme — what if it still does not appear?

If FS9.cfg sigue sin salirme, meaning it still does not appear, verify that the simulator can start and write settings under the same Windows profile.

1. Open the parent folder: Enter %APPDATA% in Run, then open Microsoft and FS9 manually if those folders exist.
2. Generate the file: Start FS2004, reach the main screen, change one harmless option, and exit normally.
3. Check the actual user: If FS2004 was launched with Run as different user, its configuration belongs to that other account.
4. Check startup failure: If FS2004 crashes or closes before reaching its main screen, use our FS2004 startup-crash checks before expecting a new file to appear.

Is the file called FS9.cfg, user.cfg or 9FS004-031?

The main per-user configuration file for Microsoft Flight Simulator 2004 is FS9.cfg; neither user.cfg nor 9FS004-031 is its standard filename.

FS9 is the common shorthand for Flight Simulator 2004 and comes from names such as the simulator executable, fs9.exe. A file called user.cfg may belong to another program or add-on, but it should not be substituted for or renamed to FS9.cfg.

Likewise, 9FS004-031 is not the standard FS2004 configuration filename or folder path. If that identifier appears on media, packaging, a download or separate documentation, its meaning belongs to that specific item; it does not change where Windows stores FS9.cfg.

How can I confirm which FS9.cfg file is active?

The active copy is the one whose modification time changes after you alter an FS2004 setting and exit the simulator normally.

1. Close FS2004 and open %APPDATA%\Microsoft\FS9.
2. Note the file’s modification time and make a backup.
3. Start FS2004 and change an easily reversible option.
4. Exit normally, then inspect the file again.
5. Confirm the result: If its modification time changed, that is the copy FS2004 updated. If it did not, check the Windows account and make sure you did not select a search result from an installation or VirtualStore folder.

Can I safely reset or rebuild FS9.cfg?

Yes. Renaming the active FS9.cfg makes FS2004 generate a clean default file on its next successful start, while preserving the old copy for recovery.

1. Close FS2004.
2. Enable file extensions so the complete filename is visible.
3. Rename FS9.cfg to FS9.cfg.old.
4. Start FS2004 and allow it to create a replacement.
5. Test the clean configuration before restoring any customised entries.

This can reset display, sound, control and other preferences, but it does not delete installed aircraft or scenery files. If the clean file solves a crash or corrupted setting, reapply changes individually rather than copying the old file back wholesale. See our full restore and rebuild procedure for FS9.cfg for recovery choices.

How should I edit FS9.cfg without losing changes?

Edit the confirmed active file with a plain-text editor while FS2004 is closed, and change only one setting at a time.

1. Back up the original outside the FS9 folder.
2. Open FS9.cfg in a plain-text editor rather than a word processor.
3. Change one entry so any unwanted result is easy to identify and reverse.
4. Save the existing file with the exact name FS9.cfg.
5. Start and test FS2004 before making another adjustment.

If a change does not persist, confirm that you edited the active copy, that FS2004 was closed during the edit, and that the file is not marked Read-only. Old tweaks can be hardware-dependent, so use our practical FS9.cfg graphics and mod guidance rather than copying large configuration blocks without checking what each setting does.