Create Appointment in Nintex Workflow - Finding the right certificate

Error: "The root of the certificate chain is not a trusted root authority"

this blog has a very good explanation of why you are receiving the issue: http://blogs.perficient.com/microsoft/2011/03/how-to-create-an-outlook-appointment-using-nintex-workflow-2010/

However, the solution for adding the correct Root Certificate was a bit sloppy in my opinion.  As the script below adds ALL the certificates (which in my case was about 100 of them, very messy!):

foreach ($cert in (Get-ChildItem cert:LocalMachineRoot)) { if (!$cert.HasPrivateKey) {New-SPTrustedRootAuthority -Name $cert.Thumbprint -Certificate $cert } }

When you only need to add one.  The one it's referencing.  It should be referencing your Outlook Web Access URL (Webmail).  You know, the URL you input in the Appointment Configuration Settings.

If that's the case, here's how to download the right certificate and keep a nice clean Certificate List in SharePoint:

• navigate to your Webmail address
• click the Lock icon next to your HTTPS url
• View the Certificate (different ways in different browsers)
• Click the Details Tab
• Click Copy To File
• Select DER encoded Binary X.509
• Choose a filename and save.
• Now you've got the right certificate, upload it to Central Admin via Security > Manage Trust

Re-run your workflow and revel in the glory of success.