Appinstaller cannot install .msix from URI following Windows Update KB5018418

[haakonfp]

Following the Windows security update KB5018418, our Appinstaller no longer works with an MSIX accessed through a URI. This used to work (and still works) for machines that do not have the Windows update applied.

On machines that have the Windows update applied, the appinstaller recognizes the package details, but on install returns:

Appinstaller operation failed with error code 0x80072F8F. Detail: Unknown error (0x80072f8f).

Our appinstaller uses an MSIX hosted in Google Cloud Storage. We have also tried hosting in AWS S3, but this resulted in the same error.

The error 0x80072f8f is pretty vague, and I have seen it be returned in multiple cases with different error messages. When googling, it seems most users have this error code in relation to Windows updates, an unsynced local time/zone, and/or Windows activation and product key issues. This cannot be the case here, as it happens on all machines we have tested on (10+), and all have a synced time/zone, and all have activated Windows licenses..

I am in dialogue with Google Cloud support to rule out an error on their end, but so far in the investigation, everything points to the Windows update rather than an issue on the MSIX host/endpoint side. This is also supported by the fact that the AWS S3 endpoint does not work.

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Appinstaller and error outputs

Error shown in the Appinstaller Window (parts are in Norwegian, sorry):

Error returned when attempting install from PowerShell:

Checking the Event Log entry:

The Event Viewer log entry provides no more information. A netsh trace provided no useful information either.

I have tried resetting Microsoft Store and followed a variety of other troubleshooting steps suggested for the error code. None have solved the issue on any of the machines we have tested on.

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Summary

• Installing as part of building/running in Visual Studio works.
• Installing directly via the MSIX locally works.
• Downloading from the S3 or Cloud Storage endpoint and then installing with MSIX works.

However,

• Appinstaller is NOT able to install after the Windows update is applied.

Is this a known issue? Is this an error on the Appinstaller program's end or Windows' end?

[wenyue]

I have confirmed, at least on my end, that it is related to SSL, TLS handshakes So please use http instead of https

[rhelaers]

Did you ever find a cause/solution to this problem? It is indeed related to SSL, we found that with a certain SSL certificate the problem occurs, when we use a self-signed certificate as a test, the error no longer occurs. But we have no idea which setting/property... it could be