I followed the steps below in Option 2. It provided me a certificate, however it expired in August 2016(approximately 3 months before I posted this), therefor the issue still exists. Is there an updated procedure to get a valid certificate?
SOLUTION
Option 1: Un-check the Trust Center option "Require Application Add-ins to be signed by Trusted Publisher"
Option 2: Add ADFdi's public key to the trusted publisher's list.
- See below for the steps to obtain the correct public key.
- Then, refer to Microsoft documentation for instructions on how to add the certificate to the Trusted Publisher list.
How to obtain ADFdi's public key:
- Locate the ADFdi installer
- Show the properties and click on Digital Signatures
- Select the signature and click on Details
- Click on View Certificate
- Select the Details tab
- Scroll down and select Public Key
- Click "Copy to file..."
Microsoft documentation reference: Add, remove, or view a trusted publisher