Install Root CA Certificate

Use the following PowerShell code to add your Enterprise Root CA certificate into SharePoint.

Add-PSSnapin microsoft.sharepoint.powershell

$CertPath = 'C:\Install\MeetingMAnager\Contoso-Root-CA.cer'

$CertName = 'Contoso Root CA'

# Get the certificate

$certificate = New-Object System.Security.Cryptography.X509Certificates.X509Certificate2($CertPath)

# Make the certificate a trusted root authority in SharePoint

New-SPTrustedRootAuthority -Name $CertName -Certificate $certificate 

After that, please run "iisreset /noforce" otherwise the change will take one day to take effect: