A quick post with some notes on how to solve this issue. When running apt update and apt upgrade on Ubuntu I received this error message:

Errors were encountered while processing: sa-compile E: Sub-process /usr/bin/dpkg returned an error code (1)

So I tried running sa-compile myself which returned the following:

sa-compile: not compiling; 'spamassassin --lint' check failed!

It wasn’t obvious to me at first but running spamassassin --lint helped. It lead me to my main.cf which I had changed and never checked 😖

After fixing the offending line, I was able to restart spamassassin, run sa-compile and update successfully.

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