Does anyone else have login issues when upgrading from .NET Core 2.1 to 3.1
Application Type
Traditional Web
Platform Version
11.12.2 (Build 31091)

Hi all,

The latest Platform Server version 11.12.2 requires Microsoft .NET Core Windows Server Hosting 3.1 installed. Does anybody else have an issue with removing Microsoft .NET Core Windows Server Hosting 2.1 after patching to Platform Server 11.12.2?

These were my running versions before the patch:

  • Platform Server 11.12.0
  • Microsoft .NET Core Windows Server Hosting 2.1.27

These are the steps I took to install the patch (following the checklist):

  • Verified that .NET Framework 4.8 and Build Tools 2015 is installed
  • Installed Microsoft .NET Core Windows Server Hosting 3.1.17 and did an "iisreset" (at this point both 2.1.27 and 3.1.17 are installed on the server)
  • Ran the Platform Server installation executable and completed all the installation steps in the checklist
  • Uninstall Microsoft .NET Core Windows Server Hosting 2.1.27 and did an "iisreset"

After this step, I was unable to log in to Service Center and unable to access the server.api and server.identity health checks.

I was only able to log in to Service Center after reinstalling Microsoft .NET Core Windows Server Hosting 2.1.27.

Managed to figure out what was the problem.

.NET 2.1 and 3.1 cannot be installed at the same time or else the server.api and server.identity IIS sites will try to version 2.1.

I fixed my issue by fully uninstalling .NET Core 2.1 first, and then installing .NET Core 3.1. After a restart of the IIS, the server.api and server.identity IIS sites did not throw any more errors.

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