Unable to upload new root certificate to vCenter WebUI - Error occurred while adding trusted root certificates: java.lang.String, null

Products

• VMware vCenter Server 7.0
• VMware vCenter Server

Issue/Introduction

When navigating to Administration > Certificates > Certificate Management > Trusted Root Certificates > ADD it won't add the root certificate giving the error 

Error occurred while adding trusted root certificates: java.lang.String, null

Cause

Certificate is not in the correct PEM base-64 format and can't be decoded.  See certificate requirements here

Certificate Requirements for Different Solution Paths

Resolution

Ensure the certificate is in base-64 encoded format and it looks like the below in a text editor

-----BEGIN CERTIFICATE-----

<CERTIFICATE ENCODING> 

-----END CERTIFICATE-----

This can be done in Windows

1. Open certificate by double-clicking a certificate file
2. Switch to the Details tab of the Certificate dialog and then click Copy to File.
3. Click Next in the Certificate Export Wizard window and then select Base-64 encoded X.509 (.CER) on the Export File Form screen and then click Next.
4. Click Browse or enter a File name and click Next then click Next and Finish.