Can't start server process

[LandyVlad]

I preface this by saying - Please forgive any errors / things I've missed - this is my first time using Jellyfin (and I am not very knowledgeable about github)

PC running Windows 11 OS.
Jellyfin server version 10.10.7 installed via Windows Installer
It actually did work the first time but I didn't have much time to play with it. Today when I started my computer I get a pop up error box "Could not start Jellyfin server process after the specified wait period. You can find the server logs at c:\ProgramDaata\jellyfin\server\log"

The jellyfin icon appears in the system tray. Autostart is set. If I right click icon and click 'start jellyfin' it produces the above error again.


Contents of server log:

[2025-09-30 13:52:40.722 +10:00] [INF] [1] Main: Jellyfin version: "10.10.7"
[2025-09-30 13:52:40.734 +10:00] [INF] [1] Main: Environment Variables: ["[JELLYFIN_LOG_DIR, C:\ProgramData\Jellyfin\Server\log]"]
[2025-09-30 13:52:40.736 +10:00] [INF] [1] Main: Arguments: ["C:\Program Files\Jellyfin\Server\jellyfin.dll", "--datadir", "C:\ProgramData\Jellyfin\Server"]
[2025-09-30 13:52:40.737 +10:00] [INF] [1] Main: Operating system: "Microsoft Windows 10.0.26100"
[2025-09-30 13:52:40.738 +10:00] [INF] [1] Main: Architecture: X64
[2025-09-30 13:52:40.739 +10:00] [INF] [1] Main: 64-Bit Process: True
[2025-09-30 13:52:40.740 +10:00] [INF] [1] Main: User Interactive: True
[2025-09-30 13:52:40.740 +10:00] [INF] [1] Main: Processor count: 16
[2025-09-30 13:52:40.741 +10:00] [INF] [1] Main: Program data path: "C:\ProgramData\Jellyfin\Server"
[2025-09-30 13:52:40.741 +10:00] [INF] [1] Main: Log directory path: "C:\ProgramData\Jellyfin\Server\log"
[2025-09-30 13:52:40.742 +10:00] [INF] [1] Main: Config directory path: "C:\ProgramData\Jellyfin\Server\config"
[2025-09-30 13:52:40.742 +10:00] [INF] [1] Main: Cache path: "C:\ProgramData\Jellyfin\Server\cache"
[2025-09-30 13:52:40.743 +10:00] [INF] [1] Main: Temp directory path: "C:\Users\landyvlad\AppData\Local\Temp\jellyfin"
[2025-09-30 13:52:40.744 +10:00] [INF] [1] Main: Web resources path: "C:\Program Files\Jellyfin\Server\jellyfin-web"
[2025-09-30 13:52:40.744 +10:00] [INF] [1] Main: Application directory: "C:\Program Files\Jellyfin\Server\"
[2025-09-30 13:52:41.218 +10:00] [FTL] [1] Main: Unhandled Exception
System.InvalidOperationException: There is an error in XML document (1, 1).
---> System.Xml.XmlException: '.', hexadecimal value 0x00, is an invalid character. Line 1, position 1.
  at System.Xml.XmlTextReaderImpl.Throw(Exception e)
  at System.Xml.XmlTextReaderImpl.Throw(String res, String[] args)
  at System.Xml.XmlTextReaderImpl.ParseRootLevelWhitespace()
  at System.Xml.XmlTextReaderImpl.ParseDocumentContent()
  at System.Xml.XmlReader.MoveToContent()
  at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationReaderMigrationOptions.Read4_MigrationOptions()
  at System.RuntimeMethodHandle.InvokeMethod(Object target, Void** arguments, Signature sig, Boolean isConstructor)
  at System.Reflection.MethodBaseInvoker.InvokeWithNoArgs(Object obj, BindingFlags invokeAttr)
  --- End of inner exception stack trace ---
  at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader, String encodingStyle, XmlDeserializationEvents events)
  at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader)
  at Emby.Server.Implementations.Serialization.MyXmlSerializer.DeserializeFromStream(Type type, Stream stream)
  at Emby.Server.Implementations.Serialization.MyXmlSerializer.DeserializeFromFile(Type type, String file)
  at Jellyfin.Server.Migrations.MigrationRunner.RunPreStartup(ServerApplicationPaths appPaths, ILoggerFactory loggerFactory)
  at Jellyfin.Server.Program.StartApp(StartupOptions options)
  at Jellyfin.Server.Program.<Main>(String[] args)
[2025-09-30 14:06:17.187 +10:00] [INF] [1] Main: Jellyfin version: "10.10.7"
[2025-09-30 14:06:17.207 +10:00] [INF] [1] Main: Environment Variables: ["[JELLYFIN_LOG_DIR, C:\ProgramData\Jellyfin\Server\log]"]
[2025-09-30 14:06:17.209 +10:00] [INF] [1] Main: Arguments: ["C:\Program Files\Jellyfin\Server\jellyfin.dll", "--datadir", "C:\ProgramData\Jellyfin\Server"]
[2025-09-30 14:06:17.210 +10:00] [INF] [1] Main: Operating system: "Microsoft Windows 10.0.26100"
[2025-09-30 14:06:17.211 +10:00] [INF] [1] Main: Architecture: X64
[2025-09-30 14:06:17.211 +10:00] [INF] [1] Main: 64-Bit Process: True
[2025-09-30 14:06:17.212 +10:00] [INF] [1] Main: User Interactive: True
[2025-09-30 14:06:17.212 +10:00] [INF] [1] Main: Processor count: 16
[2025-09-30 14:06:17.213 +10:00] [INF] [1] Main: Program data path: "C:\ProgramData\Jellyfin\Server"
[2025-09-30 14:06:17.214 +10:00] [INF] [1] Main: Log directory path: "C:\ProgramData\Jellyfin\Server\log"
[2025-09-30 14:06:17.214 +10:00] [INF] [1] Main: Config directory path: "C:\ProgramData\Jellyfin\Server\config"
[2025-09-30 14:06:17.215 +10:00] [INF] [1] Main: Cache path: "C:\ProgramData\Jellyfin\Server\cache"
[2025-09-30 14:06:17.216 +10:00] [INF] [1] Main: Temp directory path: "C:\Users\landyvlad\AppData\Local\Temp\jellyfin"
[2025-09-30 14:06:17.216 +10:00] [INF] [1] Main: Web resources path: "C:\Program Files\Jellyfin\Server\jellyfin-web"
[2025-09-30 14:06:17.217 +10:00] [INF] [1] Main: Application directory: "C:\Program Files\Jellyfin\Server\"
[2025-09-30 14:06:17.710 +10:00] [FTL] [1] Main: Unhandled Exception
System.InvalidOperationException: There is an error in XML document (1, 1).
---> System.Xml.XmlException: '.', hexadecimal value 0x00, is an invalid character. Line 1, position 1.
  at System.Xml.XmlTextReaderImpl.Throw(Exception e)
  at System.Xml.XmlTextReaderImpl.Throw(String res, String[] args)
  at System.Xml.XmlTextReaderImpl.ParseRootLevelWhitespace()
  at System.Xml.XmlTextReaderImpl.ParseDocumentContent()
  at System.Xml.XmlReader.MoveToContent()
  at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationReaderMigrationOptions.Read4_MigrationOptions()
  at System.RuntimeMethodHandle.InvokeMethod(Object target, Void** arguments, Signature sig, Boolean isConstructor)
  at System.Reflection.MethodBaseInvoker.InvokeWithNoArgs(Object obj, BindingFlags invokeAttr)
  --- End of inner exception stack trace ---
  at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader, String encodingStyle, XmlDeserializationEvents events)
  at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader)
  at Emby.Server.Implementations.Serialization.MyXmlSerializer.DeserializeFromStream(Type type, Stream stream)
  at Emby.Server.Implementations.Serialization.MyXmlSerializer.DeserializeFromFile(Type type, String file)
  at Jellyfin.Server.Migrations.MigrationRunner.RunPreStartup(ServerApplicationPaths appPaths, ILoggerFactory loggerFactory)
  at Jellyfin.Server.Program.StartApp(StartupOptions options)
  at Jellyfin.Server.Program.<Main>(String[] args)
[2025-09-30 19:48:24.984 +10:00] [INF] [1] Main: Jellyfin version: "10.10.7"
[2025-09-30 19:48:25.003 +10:00] [INF] [1] Main: Environment Variables: ["[JELLYFIN_LOG_DIR, C:\ProgramData\Jellyfin\Server\log]"]
[2025-09-30 19:48:25.005 +10:00] [INF] [1] Main: Arguments: ["C:\Program Files\Jellyfin\Server\jellyfin.dll", "--datadir", "C:\ProgramData\Jellyfin\Server"]
[2025-09-30 19:48:25.007 +10:00] [INF] [1] Main: Operating system: "Microsoft Windows 10.0.26100"
[2025-09-30 19:48:25.007 +10:00] [INF] [1] Main: Architecture: X64
[2025-09-30 19:48:25.008 +10:00] [INF] [1] Main: 64-Bit Process: True
[2025-09-30 19:48:25.009 +10:00] [INF] [1] Main: User Interactive: True
[2025-09-30 19:48:25.009 +10:00] [INF] [1] Main: Processor count: 16
[2025-09-30 19:48:25.010 +10:00] [INF] [1] Main: Program data path: "C:\ProgramData\Jellyfin\Server"
[2025-09-30 19:48:25.011 +10:00] [INF] [1] Main: Log directory path: "C:\ProgramData\Jellyfin\Server\log"
[2025-09-30 19:48:25.011 +10:00] [INF] [1] Main: Config directory path: "C:\ProgramData\Jellyfin\Server\config"
[2025-09-30 19:48:25.012 +10:00] [INF] [1] Main: Cache path: "C:\ProgramData\Jellyfin\Server\cache"
[2025-09-30 19:48:25.013 +10:00] [INF] [1] Main: Temp directory path: "C:\Users\landyvlad\AppData\Local\Temp\jellyfin"
[2025-09-30 19:48:25.013 +10:00] [INF] [1] Main: Web resources path: "C:\Program Files\Jellyfin\Server\jellyfin-web"
[2025-09-30 19:48:25.014 +10:00] [INF] [1] Main: Application directory: "C:\Program Files\Jellyfin\Server\"
[2025-09-30 19:48:25.490 +10:00] [FTL] [1] Main: Unhandled Exception
System.InvalidOperationException: There is an error in XML document (1, 1).
---> System.Xml.XmlException: '.', hexadecimal value 0x00, is an invalid character. Line 1, position 1.
  at System.Xml.XmlTextReaderImpl.Throw(Exception e)
  at System.Xml.XmlTextReaderImpl.Throw(String res, String[] args)
  at System.Xml.XmlTextReaderImpl.ParseRootLevelWhitespace()
  at System.Xml.XmlTextReaderImpl.ParseDocumentContent()
  at System.Xml.XmlReader.MoveToContent()
  at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationReaderMigrationOptions.Read4_MigrationOptions()
  at System.RuntimeMethodHandle.InvokeMethod(Object target, Void** arguments, Signature sig, Boolean isConstructor)
  at System.Reflection.MethodBaseInvoker.InvokeWithNoArgs(Object obj, BindingFlags invokeAttr)
  --- End of inner exception stack trace ---
  at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader, String encodingStyle, XmlDeserializationEvents events)
  at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader)
  at Emby.Server.Implementations.Serialization.MyXmlSerializer.DeserializeFromStream(Type type, Stream stream)
  at Emby.Server.Implementations.Serialization.MyXmlSerializer.DeserializeFromFile(Type type, String file)
  at Jellyfin.Server.Migrations.MigrationRunner.RunPreStartup(ServerApplicationPaths appPaths, ILoggerFactory loggerFactory)
  at Jellyfin.Server.Program.StartApp(StartupOptions options)
  at Jellyfin.Server.Program.<Main>(String[] args)

This tech info doesn't mean much to me - I'd appreciate if someone could decipher / suggest how to fix the issue.  Ta.


Also an aside - do I need both the server and a separate client on my windows machine - or clients only on external streaming devices (phone, TV, google cast etc)

Thank you for your patience.

[Haioken]

There is an XML document that Jellyfin is opening and attempting to read. However, when reading the contents, it's simply not XML data.
This can be determined by the first error:

Code:

System.InvalidOperationException: There is an error in XML document (1, 1).
---> System.Xml.XmlException: '.', hexadecimal value 0x00, is an invalid character. Line 1, position 1.

The fact that line 1 position 1 is a null byte (0x00) indicates an empty file, but Jellyfin is not indicating what file it's attempting to read here. I'd hazard a guess that it's probably system.xml

Without access to your system I can't tell you why the file is empty (or perhaps unreadable).
My suggestion would be to uninstall and reinstall at this point.
I don't mean this in an unpleasant way, but if you're unable to determine the nature of the startup failure from the logs, I don't fancy your chance of debugging the issue or repairing the existing installation.

I am not affiliated with the Jellyfin team, they might be more helpful, but honestly I think the most likely problem here is that you have inadvertently removed or emptied a file you shouldn't have touched.

[LandyVlad]

Thanks. I revoUninstaller and got rid of it and reinstalled from exe file.
Now getting cant connect to a server. I'm a bit confused will need to read up on it more.
Cheers

[theguymadmax]

You most likely need to clear your cache. Try opening the page in a private browser window.

[LandyVlad]

Um well if I open in incog it just shows same thing but instead of name of PC it just has 'undefined' and its no clickable at all,. so no error.

It's odd because it's like I'm trying to start a server and it wants me to connect to a server. How do I start the server in the first place?