Tes4Mod:Oblivion Script Extender

OBSE and its plugins are not "regular" mods and require a different kind of installation, which is why their installation is covered here. Most of the following are stabilizers, all highly recommended. The two most vital OBSE plugins are Fast Exit V2 and OSR!
:Note: 1) The DLLs for all OBSE plugins should be installed to  . 2) Some OBSE plugins have dependencies (DLLs) in subfolders of that folder as well.

Installation
  Steam users!!! OBSE will not work if this setting is not enabled: Steam > Settings > In-Game > Check the box marked "Enable steam community in-game".

# Download Oblivion Script Extender (OBSE) to the Oblivion folder
# Extract it there. (It will add a folder containing the OBSE files.)
# Copy the following up into the Oblivion folder: "obse_1_2_416.dll", "obse_editor_1_2.dll", and "obse_loader.exe." If you use the Steam version, move "obse_steam_loader.dll" as well.
#:Note: Steam users do not need the EXE to launch the game with OBSE, but some scripts (primarily OMOD scripts) check for the presence of that files. The presence of the EXE will not cause problems.
# Delete the folder and the archive it added.
#:Note: 1) from now on!! use the obse_loader.exe to launch your game, launching the game with OBSE-''dependent plugins (not OBSE plugins) installed guarantees a crash, so it is best to get used to always using this launcher 2) If upon launching, it errors about needing the latest version of Oblivion installed (1.2.0416), you need to install the latest patch (via installing the second disc, if you are a GOTY user.)

OBSE Plugins

OBSE plugins have quite a different package composition. The installation is very consistent, but the packaging is not. All OBSE plugins are installed to the  . Some plugins are packed such that they can be extracted into the Oblivion folder for proper installation; others require installing directly to the OBSE Plugins folder (which may need to be created.)

'Installation steps for some common OBSE plugins...''

# Download the following OBSE plugins:  
#* Elys' Universal Silent Voice (USV) - extends time text is displayed on screen for unvoiced dialog, so that it does not just flash
#* Fast Exit v2 - prevents CTD on exit
#* Oblivion Stutter Remover (OSR) - manages memory at a low level, reducing stuttering in-game
#* Pluggy - extends OBSE, especially for debugging, for mods and the user
# Install the archives: Extract Fast Exit and OSR in the Oblivion folder. Extract Elys' USV in the Data folder. Extract Pluggy into the OBSE plugins folder (Oblivion\Data\OBSE\Plugins, which you may have to create). All of the DLLs should end up directly in the Plugins folder (except for OSR's component DLLs which should be in their own subfolder.)
#:Note: All OBSE plugins are installed in the above folder. That is where you will find the INIs that needed to be tweaked for your OBSE plugins (not OBSE-dependent mods.) The "src" folder directly underneath the Oblivion folder is not for mod users. Let it be.
# Find the "Oblivion Stutter Remover" thread on the BethSoft forums before tweaking the INI file. The safest edit you can make is to raise the FPS cap.
#:''Note: If you have a very good computer, you may want to raise the cap to 60 FPS. If you use Streamline, turn off Streamsmooth or set SL's FPS range inside of OSRs. OSR is more robust, and they can cause bad conflicts when vying to handling memory management.''
# Another OBSE plugin: If you are going to use Elys' Uncapper, (uncaps the level for the PC skills and attributes, raising the limit from 100 to 200 or 255) extract it to (or in) the OBSE plugins folder.

See Also
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