I switched to qmail when I had an exchange server (early 2000s) that I spent days trying to figure out a configuration problem which finally lead me to emailing

I switched to qmail when I had an exchange server (early 2000s) that I spent days trying to figure out a configuration problem which finally lead me to emailing MS Support. Their suggestion was to just back everything up and reinstall. Sometimes that would fix it. I spent the next 2 days meticulously setting up my RHL/Qmail server and never had an issue. Ran like a champ until that startup died.