MSFS's VFS system

The Virtual File System (VFS) in Microsoft Flight Simulator (MSFS) is like a big organizer for all the game's files. Imagine it as a big library where everything the game needs – like aircraft, sceneries, avionics, and much more – is stored. It helps the game find and use these files easily.

Structure of VFS in MSFS

The VFS in MSFS acts like a set of layers: Core packages, Official packages and Community packages. It makes all the different files look like they're in one place, even if they're not. When there are multiple versions of a file, the game uses the latest one loaded, typically located in the Community folder.

How MSFS Add-ons Work with VFS

Add-ons in MSFS are modified or added files that users can install to enhance or modify the game. These can range from new aircraft models to altered menu systems like Flow. When you install an add-on in your Community folder or via the in-sim Marketplace, it gets added to the VFS, allowing the game to recognize and use the new/altered files during gameplay. The VFS ensures that these files are correctly referenced and loaded.

Conflicts Between MSFS Add-ons

In Microsoft Flight Simulator (MSFS), conflicts can arise when two add-ons attempt to modify the same game element, such as a font file, avionics, visual effects, textures, among others. In the VFS, if there are files with the same name from different add-ons or core packages, the game only uses the file from the add-on that loads last, typically found in the Community folder.

For example, if multiple add-ons change the same font file, it could lead to issues with avionics, tail registration, or other user interface elements, causing them not to display correctly.

Additionally, add-ons in MSFS are loaded alphabetically. In cases of conflict, the package whose name comes later in the alphabet will override the other. Managing these conflicts requires careful organization of add-ons and, sometimes, the use of add-on management tools like Simstaller.

Core File Replacement

Some add-ons change important game files. This might be required for the add-on to function properly but might lead to unexpected behaviors in some situations. This can be tricky because some of these files are used in many parts of the game. If an add-on changes a file that other parts of the game use too, like a multitude of aircraft, it can cause unexpected problems. For example, if an add-on changes a file for one plane's instruments, it might accidentally change the instruments for some/all planes in the game, not just the one the add-on was meant for.

Managing Add-on Conflicts

The key to managing these conflicts is understanding the scope of each mod and carefully organizing them. It's crucial to ensure that mods don't overlap in their modifications unless they are designed to be compatible. Tools like Simstaller allow you to navigate the VFS and find conflicts.


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