Postfix issue on Mac OS X 10.12.6 I'm using Postfix to forward emails from my Mac through smtp.gmail.com.

Following recent security update (https://support.apple.com/en-us/HT208221) Postfix fails to forward emails with the following errors:

smtp: warning: Digest algorithm "md5" not found
smtp: warning: disabling TLS support
smtp: TLS is required, but our TLS engine is unavailable


Here is a snippet from Postfix main.cf.

relayhost = [smtp.gmail.com]:587
smtp_generic_maps = hash:/etc/postfix/generic
smtp_tls_security_level=encrypt
smtp_sasl_auth_enable=yes
smtp_sasl_password_maps=hash:/etc/postfix/sasl/passwd
smtp_sasl_security_options = noanonymous
smtp_sasl_mechanism_filter = plain


Any ideas how to get this working again?
I also upgraded to High Sierra and that fixed the issue for me. I have been trying for a week to find a solution.