Lync/Skype4B Certificate Store Validation

https://blogs.technet.microsoft.com/uclobby/2015/06/19/checks-to-do-in-the-lyncskype4b-certificate-store/

Check #1 - Misplaced certificates in Trusted Root CA

Check #2 - Duplicates in Trusted Root CA

Check #3 - More than 100 certificates in Trusted Root CA

Check #4 - Root CA certificates in Personal Store

Check #5 - Duplicated Friendly Name

Check #6 - Misplaced Root CA certificates in Intermediate CA store (Suggested in the comments)

Get-Childitem cert:\LocalMachine\root -Recurse | Where-Object {$_.Issuer -ne $_.Subject} | Select Issuer, Subject, Thumbprint | fl

Get-Childitem cert:\LocalMachine\root | Group-Object -Property Thumbprint | Where-Object {$_.Count -gt 1} | Select-Object -ExpandProperty Group | Select FriendlyName, Issuer, Subject, Thumbprint | fl

Get-Childitem cert:\LocalMachine\root | Measure

Get-Childitem cert:\LocalMachine\my -Recurse | Where-Object {$_.Issuer -eq $_.Subject} | Select FriendlyName, Issuer, Subject, Thumbprint | fl

Get-Childitem cert:\LocalMachine\my | Group-Object -Property FriendlyName | Where-Object {$_.Count -gt 1} | Select-Object -ExpandProperty Group | Select FriendlyName, Issuer, Subject, Thumbprint | fl

Get-ChildItem Cert:\localmachine\CA | Where-Object {$_.Issuer -eq $_.Subject} | Select Issuer, Subject, Thumbprint | fl