E Mail settings

I purchased System Admin pro, so that I could setup email from the gui. Because the server I use does not support encryption I had to change the security settings of sasl in main.cf. After that the mail worked. Because I had to change another setting I changed in the gui somtehing and submitted. Then the email didn’t work anymore. After some searching I found out that the change I made in main.cf was overwritten and the security settings of sasl was back to previous. How can I change this in such a manner that these settings are not overwritten every time i change something to the email settings?