ACNM: Dependency provider use the same key for both arm64 and x64

[joeloff]

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

When support for arm64 was introduced to ANCM, the provider key used by the installer was not updated. The dependency provider is used to reference count installations and should track x64 and arm64 installs separately.

This was discovered as part of a customer investigation where ANCM was removed during an upgrade. The provider key was not the root cause of the investigation, but can result in installers making incorrect decisions.

aspnetcore/src/Installers/Windows/AspNetCoreModule-Setup/ANCMV2/AncmV2.wixproj

Lines 18 to 19 in cc983ac

	<ANCMDepProviderKey Condition="'$(Platform)' == 'x86'">IIS_AspNetCore_Module_V2,x86</ANCMDepProviderKey>
	<ANCMDepProviderKey Condition="'$(Platform)' != 'x86'">IIS_AspNetCore_Module_V2,x64</ANCMDepProviderKey>

. I think the provider key should just include the lower invariant of the platform in the key.

The issue is present in 8, 9, 10 and 11.

Note for testing: ANCM supports major upgrades, which triggers prior to running the removal of the hosting bundle. While the fix is simple, all the upgrade, repair scenarios should be verified.

Expected Behavior

No response

Steps To Reproduce

No response

Exceptions (if any)

No response

.NET Version

No response

Anything else?

No response

[github-actions]

Triage Summary

Area: area-infrastructure — The bug is in the WiX installer project at src/Installers/Windows/AspNetCoreModule-Setup/ANCMV2/AncmV2.wixproj, which falls under the infrastructure/installer area.

Type: bug — The ANCM dependency provider key was not updated when arm64 support was added (PR #38997), causing both x64 and arm64 installations to share the same reference-count key. This can lead to incorrect installer decisions (e.g., unintended removal of ANCM during upgrades).

Potential Duplicates

• None found

Notes

• The bug was introduced when arm64 support was added and affects .NET 8, 9, 10, and 11.
• The fix is straightforward (include the platform/architecture in the provider key), but upgrade, repair, and major-upgrade scenarios all need verification before shipping.
• The author notes that ANCM major upgrade support triggers before the hosting bundle removal, which makes proper provider key scoping important for safe upgrades.

Generated by Issue Triage Agent for dotnet/aspnetcore for issue #65953 · ◷

[MihuBot]

I'm a bot. Here is a possible related and/or duplicate issue (I may be wrong):

• Windows hosting bundle upgrade breaks ANCM on ARM64 machines #60764

[joeloff]

I'm a bot. Here is a possible related and/or duplicate issue (I may be wrong):

• Windows hosting bundle upgrade breaks ANCM on ARM64 machines #60764

Not related, not a duplicate. That issue was related to incorrect authoring of shared components.