Please make sure that you completed these steps to ensure you’ve set the Mac up properly to accept remote building:
- Open the System Preferences > Sharing on the Mac machine
- Check the Remote Login checkbox
- Open System Preferences > Networking
- Open Keychain Access
- Select System from the left hand menu
- Select Certificates from the left hand menu
- Select one of the installed certificates
- Right click on the certificate and select Get Info
- Expand the Trust options
- Set When using this certificate: to Always Trust (setting this will all of the sub options)