How to work around Windows Phone SDK 8.0 installation failure caused by invalid digital certificate

UPDATE - A new Windows Phone SDK 8.0 setup package has been published that contains a fix for this issue. The original workaround is no longer needed.

Recently, an issue came up that can cause the Windows Phone SDK 8.0 to fail to install on 64-bit versions of Windows 8 or Windows 8.1.  This issue will cause setup to fail and report an error like the following:

A required certificate is not within its validity period when verifying against the current system clock or the timestamp in the signed file.

Microsoft has published a knowledge base article with steps you can use to work around this issue.  You can find the knowledge base article at http://support.microsoft.com/kb/2897627.  Here is a quick summary of the steps listed there:

  1. Uninstall the partially installed Windows Phone SDK 8.0 if it currently installed on your computer.
  2. Download and install the updated setup package
    1. Web downloader - http://www.microsoft.com/en-us/download/details.aspx?id=35471
    2. ISO - http://go.microsoft.com/fwlink/?LinkID=257234

Here is the previous workaround that was published prior to the updated setup package being published:

  1. Uninstall the partially installed Windows Phone SDK 8.0 if it currently installed on your computer.

  2. Download the .msi and .cab files from the following 4 locations and save them to the same folder on your computer:

    http://go.microsoft.com/fwlink/?LinkId=257143
    http://go.microsoft.com/fwlink/?LinkId=257144
    http://go.microsoft.com/fwlink/?LinkId=257145
    http://go.microsoft.com/fwlink/?LinkId=257146

  3. Go to the folder that you saved the files to and run Win8SharedSDKTools.msi file.

  4. After installing Win8SharedSDKTools.msi, re-run Windows Phone SDK 8.0 setup and install like normal.

<update date="10/11/2013"> Added a step about uninstalling the Windows Phone SDK 8.0 first if there is a partially installed version on the computer from a previous failed install. </update>

<update date="10/17/2013"> Added information about the new setup package that contains a fix for the invalid digital certificate issue. </update>