Therefore, all installed mods are loaded and used normally. When the game is started by MO, it is unaware of this VFS and thinks it uses the regular Windows file system. It is called virtual because it does NOT exist on the regular file system and only exists when MO tells a program it exists. It never writes files to the game data directory, but instead creates and uses a virtual filing system (VFS). Mod Organizer takes a very different and revolutionary approach. Unfortunately, this is not always the case, and problems may arise. If these programs work perfectly and Windows works perfectly, no harm will be done to the file system and the game continues to work.

Depending on the performed actions this can take considerable time. When using Profiles and changing the order in which mods were installed, these programs make changes to the windows file system by copying/deleting files on it. These programs have algorithms to restore files on the FS when, for example, mod B, which had overwritten files from mod A, is uninstalled. Hence the once empty and pristine state of the game data directory is lost. All files are added to the original game data directory. The user is given the option to overwrite such files. This allows them to detect if a mod overwrites files of the original game and/or one or more existing mods. When installing mods, they keep a record of all installed files. Typical mod managers like NMM and WB install mods into the data directory of the game being modded. Hence plugins like ENB and SKSE cannot be installed by them. Note: Mod managers like Nexus Mod Manager (NMM), Wrye Bash (WB) and Mod Organizer (MO) can only install files in the /data directory. The behavior of Skyrim can be changed by installing mods and plugins. The same is true when you install the official DLC's. When Skyrim is installed it stores all its files on the file system (FS) of a disk. It will be discussed for Skyrim but is valid for all four supported games. This section will not only discuss the technical details and challenges of this approach, but also its advantages and disadvantages. This provides for an untouched game data folder, void of installed mods, which is the main feature of MO. Internal Mechanics The Virtual Filing System (VFS) Īs explained in the FAQ, Mod Organizer (MO) uses mod isolation, a feature in which every mod is installed into its own directory. Mod Organizer Advanced/Technical Guide - by DoubleYou & the STEP Team

Mod organizer overwrite guide