Dedicated Server Rejects Even Blank Missions as "Unsupported" After Today's Patch

[OutLord]

Hi all,

I'm running a dedicated DCS server for personal/multiplayer use and hitting a wall with mission loading. This started happening right after applying today's patch (October 23, 2025). The server starts fine but immediately rejects any mission (including a vanilla blank Caucasus .miz) as "unsupported," leading to "server_start failed: no valid missions in the list." The web GUI shows the missions in the list but greys them out on start attempt, and the server stops right after.

Setup Details:

• DCS Version: [Insert your exact version, e.g., 2.9.12 stable / openbeta—post-patch]
• Install Path: Fresh install in a new directory (e.g., C:\Games\DCS_Fresh)
• Launch Command: "C:\Games\DCS_Fresh\Bin\DCS_server.exe" --server --norender -w dcs_serverrelease
• Workspace: Isolated via -w parameter (C:\Users\Martin\Saved Games\DCS.dcs_serverrelease)
• Web GUI: Default port 8088 (reverted from custom 8089—connects fine)
• OS: Windows [10/11], no mods enabled, Caucasus map installed/verified
• Firewall: Ports forwarded (10308 UDP, 8088 TCP), running as Admin
• Note: Full client version (same install dir and Saved Games root) runs perfectly on the same machine—missions load fine in Mission Editor and Multiplayer host mode. Issue is isolated to dedicated server.

The Issue:

• Server launches and binds to ports correctly.
• GUI scans and lists missions, but on "Start," it logs "removed unsupported mission file" for each, empties the list, and fails with the errors below.
• This happens for modded missions and fresh blanks—no units, no scripts, saved directly from Mission Editor. (Client loads the same .miz files without issue.)
• GUI then throws Lua errors querying server info (e.g., "attempt to index global 'mission' (a nil value)").

Steps I've Tried (in order, with fresh workspace resets between):

1. Full Reinstall & Saved Games Reset: Deleted old install, reinstalled to new dir. Renamed root Saved Games\DCS to backup, let server recreate fresh. Also deleted/renamed workspace DCS.dcs_serverrelease multiple times to force regen.
2. Mission Placement: Created blank Caucasus mission in full client Mission Editor (New > Empty > Save to Saved Games\DCS\MissionsMultiplayer). Copied to workspace DCS.dcs_serverrelease\MissionsMultiplayer\[Blank-23102025-Caucases].miz. Tried root Saved Games\Missions too—no diff.
3. Config Edits:
   • Deleted/renamed Config\options.lua and Config\serverSettings.lua to force defaults.
   • Manually added to new serverSettings.lua: missions = { {["path"] = "MissionsMultiplayer\\[Blank-23102025-Caucases].miz", ["name"] = "Blank Caucasus Test"} }
   • Set ["Missions"] = "MissionsMultiplayer/" in options.lua.
4. Repair & Verify: Ran DCS Updater > Repair (full scan, Caucasus confirmed installed). Permissions set to full control for user on all folders.
5. Path/Workspace Tweaks: Confirmed dcs_variant.txt = "dcs_serverrelease". Tested without -w (uses root)—same rejection. No symlinks; all physical copies.
6. GUI/Browser: Tested in Incognito Chrome/Firefox, cleared cache. GUI refreshes list but still fails on start.
7. Logs Check: No other errors pre-start (e.g., tracks fixed by creating folder). Unzipped .miz—empty Scripts/Options, re-zipped.

Nothing sticks—the log always paths to root Saved Games\[mission].miz despite copies to workspace, and rejects immediately.

Relevant Log Snippet (Latest Attempt with Blank Caucasus):

text

 

2025-10-23 01:12:09.458 INFO WORLDGENERAL (Main): loading mission from: "C:\Users\Martin\Saved Games\[Blank-23102025-Caucases].miz"
2025-10-23 01:12:45.147 WARNING LOG (2572): 1 duplicate message(s) skipped.
2025-10-23 01:12:45.147 INFO ASYNCNET (Main): server has started
2025-10-23 01:12:45.148 INFO ASYNCNET (Main): server has stopped
2025-10-23 01:12:45.148 WARNING ASYNCNET (Main): removed unsupported mission file from the list: C:\Users\Martin\Saved Games\[Blank-23102025-Caucases].miz
2025-10-23 01:12:45.148 ERROR ASYNCNET (Main): server_start failed: no valid missions in the list
2025-10-23 01:07:28.807 ERROR NET (Main): Failed assert `0`

 

 

Has anyone seen this post-patch or in recent updates? Is it a path validation bug in the workspace loader? Any log tweaks or hidden configs I'm missing? Appreciate any pointers—been grinding this for hours!

Thanks,

Edited October 23 by OutLord

[OutLord]

So the latest Patch made no difference for this problem, no one can shed any light?

[Wrecking Crew]

After reading your post I updated my server to 2.9.21.16552. The server started up fine on the last mission that was running. 

For a test, I clicked on the Save icon in the missions list. For quite a long time now, 10 months? longer?, I do that Save to overwrite the previous file and I get a lower left notification that says "Mission list is empty and cannot be saved."

Now my server appears to be frozen on the mission that was running, ie the mission time is not advancing.

From the server GUI, I did a Reconnect and I see that the mission was running and the time is now correctly displayed.

I repeated the test by doing the Save and Overwrite and got the "Mission list is empty and cannot be saved." Now the Mission Time is frozen, again. In the upper right of the GUI it says in green "Server Active -- 00:08:47" and it is frozen.

I pressed Restart on the GUI and the mission has restarted.