Issues updating ADS instance from 2.6.3 to 2.6.4 : Locked out of instances because of mismatched versions

OS Name/Version: Windows 10 Pro Build 19045

Product Name/Version: 2.6.3 - 20250926.1

Platform Windows 10 Pro
System Type x86_64
Hardware Platform
CPU Model Intel(R) Core™ i7-7700K CPU @ 4.20GHz
CPU Layout 1S/4C/8T
Installed RAM 16348
Virtualization None
Network Mode Standard
Module ADSModule
Module Application Application Deployment
Loaded Plugins FileManagerPlugin, EmailSenderPlugin, WebRequestPlugin, WebhookPlugin, LocalFileBackupPlugin, CommonCorePlugin, AnalyticsPlugin
Application Name AMPService
Application Version 2.6.3.0
Codename Phobos
Tools Version 2.6.4
Release Stream Mainline
Build Spec Release
Build Date 26/09/2025 12:12
InstanceID 8aa9b382-1052-496d-922e-1b4e711ce71d
Last Executable D:\AMPDatastore\Instances\GarbageZomboid01\AMP.exe
Last Arguments +Core.Webserver.Port “8083” +Core.Webserver.IPBinding “127.0.0.1” +Core.AMP.InstanceID “********-****-****-****-************” +Core.Security.MetricsHMAKKey “**********”
Last Process ID 2848

Problem Description:
Hello, I’m currently locked out of all my instances after updating them to version 2.6.4.0, because the ADS version (2.6.3.0) is older than the instances, as ADS fails to update.
So right now, I can’t manage any of my instances apart from start or stop. Hopefully this issue is trivial and i’m missing something. But my competency stops there, so I’ll need your assistance.

Steps to reproduce:
In AMP Panel - Support and Updates - Clicking Upgrade this instance - confirm
Panel Stops, then never comes back online (waited for an hour max)
Launching AMP shows ADS still in outdated version

Actions taken to resolve so far:

  • Restarting Windows and trying again at each step below
  • Looked up updating guide :
    Tried step 2.2, installing latest AMPsetup.msi and doing it twice with repair option
    Tried Step 5 (.bat script)
  • Running Command in CMD : ampinstmgr upgrade ADS
    gets me this :
[Info/1] AMP Instance Manager v2.6.4 built 14/11/2025 00:07
[Info/1] Stream: Mainline / Release - built by CUBECODERS/buildbot on CCL-DEV
[Info/1] Stopping Instance: 'ADS01'
[Info/1] Stopping instance ADS01...
[Info/1] Waiting for instance to stop...
[Info/6] Instance ADS01 has stopped.
[Info/6] Upgrading instance ADS01
[Error/9] Failed to extract archive: End of Central Directory record could not be found.
[Error/9] InvalidDataException
[Error/9] [0] (InvalidDataException) : End of Central Directory record could not be found.
[Error/9]    at IO.Compression.ZipArchive.ReadEndOfCentralDirectory()
   at IO.Compression.ZipArchive..ctor(Stream stream, ZipArchiveMode mode, Boolean leaveOpen, Encoding entryNameEncoding)
   at IO.Compression.ZipFile.Open(String archiveFileName, ZipArchiveMode mode, Encoding entryNameEncoding)
   at ModuleShared.Utilities.ExtractZipArchiveAsync(String archivePath, String destinationPath, String currentEntryPath, String newEntryPath, String[] skipFiles, Boolean overwriteExisting, Boolean deleteArchive, RunningTask extractTask, List`1 extractedEntryPaths, Boolean noExecutableMarking, Func`2 allowExtractDelegate)
[Info/9] Upgrade successful

Despite “Upgrade succesful” the version doesn’t update.

Thank you for your time.