[uMod] 07:19 PM [Warning] Valheim server up to date (6663905). Use --force to update from the depot anyway
[uMod] 07:19 PM [Warning] Valheim already up to date (v1.0.299-develop)
[uMod] 07:19 PM [Warning] uMod WebClient already up to date (v1.0.355-develop)
[uMod] 07:19 PM [Warning] uMod Compiler already up to date (v1.0.511-develop)
[uMod] 07:19 PM [Warning] uMod Database already up to date (v1.0.399-develop)
Starting server...

Set current directory to /root
Found path: /root/valheim_server.x86_64
Mono path[0] = '/root/valheim_server_Data/Managed'
Mono config path = '/root/valheim_server_Data/MonoBleedingEdge/etc'
Preloaded 'libsteam_api.so'
Unable to load player prefs
Initialize engine version: 2019.4.24f1 (5da6f0345e82)
[Subsystems] Discovering subsystems at path /root/valheim_server_Data/UnitySubsystems
Forcing GfxDevice: Null
GfxDevice: creating device client; threaded=0
NullGfxDevice:
Version: NULL 1.0 [1.0]
Renderer: Null Device
Vendor: Unity Technologies
Begin MonoManager ReloadAssembly
Unable to find method IsLoggingEnabled in [UnityEngine.CoreModule.dll]UnityEngine.Debug
(Filename: Line: 143)

Caught fatal signal - signo:11 code:1 errno:0 addr:(nil)
Segmentation fault
Server closed unexpectedly...

Restarting server...

Please help ASAP I am a server owner and don't want the server to be offline very long

Are you using some sort of other mod with it?

No, this is a clean install. I was originally using LGSM and converted to UMOD since I don't need a password for users. New server clean install tried a new user in the home dir and root dir which is where this error is originating.

Try updating again with the --force argument with uMod.

[uMod] 07:27 PM [Error] No resource available to update for package games/valheim (pre-release: no)
[uMod] 07:27 PM [Error] Core update failure
Downloaded installer umod-webclient-1.0.105 (from manifest)
Downloaded installer umod-compiler-1.0.110 (from manifest)
Downloaded installer umod-database-1.0.105 (from manifest)
[uMod] 07:27 PM [Info] Installed 3 package(s)
[uMod] 07:27 PM [Info] App update successful

Two errors (two top lines)

umod install valheim -P --force

[uMod] 07:29 PM [Warning] Valheim server up to date (6663905). Use --force to update from the depot anyway
[uMod] 07:29 PM [Warning] Valheim already up to date (v1.0.299-develop)
[uMod] 07:29 PM [Warning] uMod WebClient already up to date (v1.0.355-develop)
[uMod] 07:29 PM [Warning] uMod Compiler already up to date (v1.0.511-develop)
[uMod] 07:29 PM [Warning] uMod Database already up to date (v1.0.399-develop)
Starting server...

Set current directory to /root
Found path: /root/valheim_server.x86_64
Mono path[0] = '/root/valheim_server_Data/Managed'
Mono config path = '/root/valheim_server_Data/MonoBleedingEdge/etc'
Preloaded 'libsteam_api.so'
Unable to load player prefs
Initialize engine version: 2019.4.24f1 (5da6f0345e82)
[Subsystems] Discovering subsystems at path /root/valheim_server_Data/UnitySubsystems
Forcing GfxDevice: Null
GfxDevice: creating device client; threaded=0
NullGfxDevice:
Version: NULL 1.0 [1.0]
Renderer: Null Device
Vendor: Unity Technologies
Begin MonoManager ReloadAssembly
Unable to find method IsLoggingEnabled in [UnityEngine.CoreModule.dll]UnityEngine.Debug
(Filename: Line: 143)

Caught fatal signal - signo:11 code:1 errno:0 addr:(nil)
Segmentation fault
Server closed unexpectedly...

Restarting server...

Same error

According to the log, you aren't using the --force argument. Are you sure you used exactly what I had?

I tried again doubting I did the first time but it still comes up with the same error and [uMod] 07:32 PM [Warning] Valheim server up to date (6663905). Use --force to update from the depot anyway.

I used the exact line: umod install valheim -P --force

Try:

umod update valheim -P --force

[uMod] 07:50 PM [Warning] Valheim server up to date (6663905). Use --force to update from the depot anyway
[uMod] 07:50 PM [Warning] Valheim already up to date (v1.0.299-develop)
[uMod] 07:50 PM [Warning] uMod WebClient already up to date (v1.0.355-develop)
[uMod] 07:50 PM [Warning] uMod Compiler already up to date (v1.0.511-develop)
[uMod] 07:50 PM [Warning] uMod Database already up to date (v1.0.399-develop)
Starting server...

Set current directory to /root
Found path: /root/valheim_server.x86_64
Mono path[0] = '/root/valheim_server_Data/Managed'
Mono config path = '/root/valheim_server_Data/MonoBleedingEdge/etc'
Preloaded 'libsteam_api.so'
Unable to load player prefs
Initialize engine version: 2019.4.24f1 (5da6f0345e82)
[Subsystems] Discovering subsystems at path /root/valheim_server_Data/UnitySubsystems
Forcing GfxDevice: Null
GfxDevice: creating device client; threaded=0
NullGfxDevice:
Version: NULL 1.0 [1.0]
Renderer: Null Device
Vendor: Unity Technologies
Begin MonoManager ReloadAssembly
Unable to find method IsLoggingEnabled in [UnityEngine.CoreModule.dll]UnityEngine.Debug
(Filename: Line: 143)

Caught fatal signal - signo:11 code:1 errno:0 addr:(nil)
Segmentation fault
Server closed unexpectedly...

Restarting server...

Same error

I don't see that method "IsLoggingEnabled" being used by us anywhere, and I've not seen any other reports of it so far, so we'd have to look into it further to see if we can reproduce the issue.