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BennaSu's avatar
BennaSu
Copper Contributor
Jul 24, 2025

Issue updating AVD app attach packages

Hi Community,

I was trying to update the app attach package but the configuration gives me error message as these:

Error expanding msix app attach package. The MSIX Application metadata expand request failed on all Session Hosts that it was sent to. Session Host: avdrftest-0, Native error when mounting CIM, HResult -2147024809, ErrorCode 87..

I used the exact same method by using msix hero to package the app folders into msix then convert to cim file and import into dedicated storage account. The updates are only targeting one of the exe file in that app folder. For that exe file, the original code base only had 3 line of new codes added in there which is for the header message.

Tried to recreate the package so many times and also update the server. Not sure what to do at this point. 

ps: this is in GCCH tenant.

Please advise!

Thanks,

1 Reply

  • Kidd_Ip's avatar
    Kidd_Ip
    MVP
    Jul 26, 2025

    Try to fix by the following:

     

    1. Install KB5060829 or Later

    Microsoft released KB5060829 on June 26, 2025, which addresses this exact issue:

    • Go to Windows Update on your session hosts.
    • Install KB5060829 or any newer cumulative update.
    • Reboot the session hosts and retry the App Attach operation.

    2. Switch to VHDX Format

    If updating isn’t feasible right now:

    • Repackage your MSIX into VHDX instead of CIMFS.
    • VHDX is more stable and not affected by the 24H2 bug.
    • Use tools like MSIX Hero or Microsoft’s MSIX Packaging Tool to convert.

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