Player Guide/Open Mod Manager

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Open Mod Manager (OMM, also written OpenModMan) is a free mod manager for Windows, originally created by Sedenion (Eri M.) and now maintained as the successor to the older OvGME. It enables and disables DCS mods non-destructively: mods live in a separate folder, OMM stages them into DCS when enabled, and restores the originals when disabled. Nothing in your DCS install is permanently overwritten.

VRS recommends OMM for any mod you install for our server. OMM solves the three problems players hit most often:

DCS updates. DCS patches frequently overwrite files that mods touch. With OMM you flip every mod off before patching, run the update, then flip them back on.
Server integrity checks. OMM lets you disable a mod for one server and re-enable it for another in seconds.
Diagnosing conflicts. When something breaks, you can disable mods one at a time to find the culprit, without reinstalling anything.

The big upgrade over OvGME: VRS publishes a network repository at https://victorromeosierra.com/Mods/repo.xml. Subscribe once in OMM and you get one-click install plus automatic update notifications for the VRS mod packs.

Installing OMM

Download OMM 1.3.5 or later from the iquercorb/OpenModMan releases page. Two flavours are offered:

Installer (OpenModMan_1-3-5-x64_setup.exe) - installs OMM like a normal Windows program. Pick this if you want a Start-menu shortcut.
Portable ZIP (OpenModMan_1-3-5-x64_Portable.zip) - unpack anywhere and run OpenModMan.exe directly. No installer.

Either is fine. There are also 32-bit (x86) builds if you need them, but the 64-bit builds are what most players want.

First-run setup

OMM organises mods as Mod Hubs (think "profile" - one per software you mod) containing one or more Mod Channels (one per destination folder). For VRS, you'll create one Hub for DCS, with one Channel targeting your DCS install folder.

Launch OMM, then:

Click File → New Mod Hub... Give it a name like DCS and pick a folder to store its config (anywhere; e.g. D:\OMM\DCS-Hub).
In the new Hub, click Edit → Add Target Location... (some builds label this Add Mod Channel...).
Fill in the Channel:

Field	What to enter
Channel name (or "Indicative name")	Anything you like, e.g. `DCS Install`.
Target Destination folder	Your DCS install folder, typically: `C:\Program Files\Eagle Dynamics\DCS World` or, for Steam installs: `C:\Program Files (x86)\Steam\steamapps\common\DCSWorld` This is the folder that contains `bin/`, `Mods/`, `Scripts/`, etc. - not your Saved Games folder.
Library folder	Leave the default (a subfolder inside the Channel's home folder). This is where mod packages will be staged.
Backup folder	Leave the default. This is where OMM stores the originals it replaces.

You only do this once. After that, OMM remembers the Hub and opens straight to the mod list.

Why the install folder and not Saved Games? OMM exists to protect you from DCS overwriting your mods on patch day, and the install folder is the one DCS patches rewrite. Mods that live there - aircraft auto-starts, script edits, anything that touches core module files - need OMM's backup-and-restore so a patch can't wipe them silently.

Saved Games is the opposite case: DCS patches don't touch it, so mods that go there (liveries, kneeboards, missions) are safe with a plain folder copy and don't need a manager.

For the specific VRS packs - what to install where, and where to download them - see Downloads.

Subscribing to the VRS repository (recommended)

The fastest way to install and stay up-to-date with VRS mod packs:

In your Hub, select the Channel you just created.
Click Edit → Target Location properties... and switch to the Network Library tab.
Click the Add Network Repository button.
Enter:
- Base URL: https://victorromeosierra.com
- Name: Mods/repo (without the .xml extension - OMM appends it automatically)
Click Test to confirm the repository is reachable, then OK to save.
Back in the main window, switch to the Network Library tab and click Query. OMM fetches the list of available mods.
Select the packs you want, click Download Selected, and OMM downloads them into your Library.
Enable them in the Library tab as usual.

When VRS publishes an update, the repo's hash for that pack changes; OMM flags an update on its next Query. Click Download again and the new version replaces the old.

Installing a mod manually

If you'd rather skip the repository and download files yourself (or for any one-off mod not in the VRS repo):

Download the mod as a .zip.
Drop the .zip directly into your Channel's Library folder. OMM picks it up automatically; no need to unpack.
In OMM, the mod appears in the Library tab with a status icon. Select it, click Install Selected (or double-click).
Launch DCS. The mod is active.

Important: do not rename the .zip. OMM (and OvGME) require the top-level folder inside the zip to match the filename. VRS_AutoStarts.zip contains a VRS_AutoStarts/ folder; rename the zip and the parse will fail.

Updating and removing mods

To update a mod to a new version (manual install only - subscribed repos handle this automatically):

In OMM, uninstall the existing version (it goes back to "available" status).
Delete the old .zip from your Library folder.
Drop the new .zip in.
Click Install Selected.

To remove a mod entirely:

Uninstall it in OMM.
Delete the .zip from your Library folder.

Never delete a Library .zip while the mod is installed - that strands the modded files in DCS with no clean way to restore the originals. Always uninstall first.

Before a DCS update

DCS patches can rewrite the same files some mods overwrite. The clean routine is:

Open OMM and uninstall everything (select all in the Library tab, click Uninstall Selected).
Quit OMM.
Run the DCS updater and let it finish.
Re-open OMM and re-install your mods.

If you forget and run the patch with mods installed, DCS may overwrite OMM's backup with the patched file, and you'll lose the ability to cleanly uninstall the mod later. In that case, delete the mod from OMM, delete the staged file, re-download a fresh copy, and re-install.

Migrating from OvGME

If you were previously using OvGME for VRS mods, do this before configuring OMM, or you'll end up with two managers fighting over the same DCS files:

In OvGME, disable every mod (select all, click "Disable Selected"). OvGME restores the original DCS files.
Verify the install dir looks clean (the Mods/aircraft/*/Cockpit/Scripts/Macro_sequencies.lua files should be back to stock or absent).
Quit OvGME. You can uninstall it if you want, or just leave it idle - it won't conflict as long as nothing is enabled.
Now follow First-run setup above to configure OMM.
Subscribe to the VRS repository or install packs manually as described.

OvGME backups and OMM backups are stored differently and not interchangeable. Don't try to import OvGME's mod list into OMM - just re-download the packs through OMM.

Bringing your existing OvGME library across

If your OvGME Mods folder contains other mods (personal weapon packs, cockpit tweaks, third-party autostarts, etc.), you don't have to re-download all of them. Copy the contents of your OvGME Mods folder into your new OMM Channel's Library folder:

Locate your OMM Channel's Library folder. In OMM, select the Channel and check Edit → Target Location properties → Local Library tab. By default it sits at <HubFolder>\<ChannelName>\Library\.
Copy every mod from your OvGME Mods folder into that Library, except VRS_AutoStarts.zip (you get that via the repo subscription instead) and any OvGME-specific README files.
In OMM's Channel properties → Local Library tab, tick Developer mode. This lets OMM recognise folder-form mods (mods that you previously unzipped into the OvGME Mods folder rather than left as .zip files). Without Developer mode, OMM only sees .zip files.
Restart OMM (or refresh the Library view). All your previous mods now appear in OMM's Library tab.

Watch for overlap. If any of your previous OvGME mods touched the same files as a VRS pack (e.g. another autostart for an airframe also covered by VRS_AutoStarts), only one can be installed at a time. Install your personal autostart or VRS_AutoStarts, not both.

Troubleshooting

The mod is installed in OMM but nothing changed in DCS. The internal folder layout of the mod is wrong - the folders inside the mod's top-level directory must match DCS's install folder layout (e.g. Mods/aircraft/FA-18C/Cockpit/Scripts/..., Scripts/...). Open a working mod and compare. (Note: if the mod is actually a livery or kneeboard, it belongs in Saved Games, not in OMM.)

OMM rejects the .zip as "unknown or wrong Mod Pack architecture". The filename and the top-level folder inside the zip don't match. VRS_AutoStarts.zip must contain a folder called exactly VRS_AutoStarts/ at its root. Don't rename downloaded zips.

DCS won't join the VRS server after installing a mod. VRS does not enforce strict integrity, but some mods (especially weapon/flight model edits) can still cause problems. Uninstall the mod, re-join, and ask in #questions on Discord before re-installing.

OMM says a file conflict / overlap occurred. Two installed mods both want to write the same file. The one installed last wins. Uninstall both, decide which one you want, install only that one.

Repository "Query" fails / 404. Double-check the Base URL is https://victorromeosierra.com (with https, no trailing slash) and the Name is Mods/repo (without .xml - OMM appends the extension itself, so writing Mods/repo.xml makes OMM fetch Mods/repo.xml.xml and 404). Confirm you can reach https://victorromeosierra.com/Mods/repo.xml in a browser - if not, the repo may be temporarily offline.