The Could Not Establish Secure Channel error is caused by the certificate not being trusted on the devices running the Recast Agent or Recast Proxy.
Resolution
Export the Recast Management Server certificate and import it to the Trusted Root Certificate Authorities store on devices running Recast Agent or Recast Proxy.
NOTE: These steps aren't required if your certificate is signed by a Certificate Authority.
Export your Recast Management Server Certificate
1. Open IIS Manager on your Recast Management Server and select the server name.
2. Double-click Server Certificates.
3. Right-click the Recast certificate and select View from the drop-down.
4. On the Details tab, click Copy To File.
5. Walk through the Certificate Export Wizard with the default settings. You will not need to export the private key.
6. Store the certificate in a location that you will be able to access from your Recast Desktop clients.
Import the Recast Management Server Certificate
1. Right-click on the certificate and choose Install Certificate.
2. When the Certificate Import Wizard opens, select Local Machine.
3. Select Place all certificates in the following store and click Browse.
4. For the Store, select Trusted Root Certificate Authorities and OK.
5. On the Certificate Store page, click Next.
6. On the Summary page. click Finish.