Download file failed signature verification and may have been tampered with - Workflow Manger 1.0 Refresh (CU2)

Since there is no major updates in Workflow Manager installation process for last couple of years, the offline installation became really difficult. Microsoft recommends to install it through WPI tool, however sometimes the online installation also becomes a nightmare. This is what happened recently.

Problem Description:

For one of our client, we had to prepare environment with following.

• SharePoint Server Enterprise 2019
• Window Server 2019 Standard
• Workflow Manager 2013

As usual I followed the same installation guide which ran fine few weeks ago with another different environment but here we faced the below error while installing Workflow Manager Refresh 1.0 (CU2).

"The product did not install successfully. Download file failed signature verification and may have been tampered with"

Tried to run the setup multiple times but nothing helped. Checked all the available discussion threads on Microsoft's and other forums but nothing helped much. However I must thanks PeterFleischer-3316 for giving an idea of manual install of the msi file.

Root Cause:

The actual root cause of this issue is still unknown. I will update this thread if I'll get a concrete reason for this error. However, there could be some reasons that I could think off.

• Security or any antivirus in your server could be causing this issue.
• There could be wrong date, time zone or Locale difference which could be the problem cause
• This issue is caused by a new policy of the Microsoft Download Center that blocks teams from offering files with SHA1 digital signatures out of security consideration, which most/all of these (Workflow Manager related) files have been codesigned with. As a result, the Microsoft Download Center is automatically unpublishing files that do not meet the new digital signature requirement.

Solution:

Since this issue is not yet recognized by Microsoft and no formal or official solution is provided on this, we have to troubleshoot and fix it ourselves by installing all the necessary prerequisites manually. Let's go step by step.

As shown in above screenshot, the first dependency is "Microsoft Windows Fabric V1 RTM" on which we are receiving this error. Before clicking the finish button on the WPI window, scroll down and click View log here. 

Or you can go to the directory directly by putting below in the explorer bar.

%LocalAppData%\Microsoft\Web Platform Installer\installers

Once the log file is open, search for "Signature" and you will directly jump to the dependency section which is creating issue. For example, it will look something like this in the logs.

Jump to this path and install this file manually. Repeat this step for all the dependencies as one by one they will give you the same error each time you run the WPI. So this has to be done for all.

Once all the dependencies are finished, the next remaining item is the Workflow Manger 1.0 Refresh (CU2) which you cannot install directly by just a double click. For this you have to play differently.

Following the above described process of finding the actual installation assembly, get the Workflow Manager Refresh MSI file from the temporary directory of Web Platform Installer. It will be Workflow_Manager.msi under a folder with some hash value.

Copy this file and place it somewhere in drive where you can locate it easily (For example D:\Temp\). Now open PowerShell and navigate to the drive path where you just pasted it. Now run below command and a setup should run to complete the Workflow Manager.

.\Workflow_Manager.msi IACCEPTEULA=yes WEBPI=1

Example: 

The story is not end yet my friend....!

Now run the Web Platform Installer again, and install Workflow Manager 1.0 Cumulative Update 5. This should go smoothly and not create any issue like above.

Bingooo...! The installation is complete and now you can follow the normal steps of configuration.

References:

https://docs.microsoft.com/en-us/answers/questions/276779/failed-to-verify-signature-workflow-manger-10-refr.html

https://docs.microsoft.com/en-us/answers/questions/271922/unable-to-download-workflow-manager-10-refresh-cu2.html

https://forums.iis.net/t/1230495.aspx

https://social.technet.microsoft.com/Forums/ie/en-US/03a9e099-b84e-4c56-a018-3493f6a78c82/failed-to-install-windows-fabric-v1-rtm-with-workflow-manger-10?forum=sharepointadmin

https://social.technet.microsoft.com/Forums/azure/en-US/1a38f77b-6ba0-4225-a77d-476e9297fffc/windown-platform-installer-fails-installing-workflow-manager-10?forum=wflmgr

https://docs.microsoft.com/en-us/answers/questions/73535/workflow-manager-10-installtion-error-on-windows-s.html

Happy SharePointing..!