- Download the latest version of MAMP
- Quit MAMP if it is running
- Browse to Applications folder and rename the MAMP directory to MAMP_OLD
- Unzip the MAMP installer and run the install
- Go to the MAMP_OLD directory, copy the db and htdocs directories, and paste into the new MAMP folder. Overwrite what is there.
- Restart MAMP
This update process works for me without any port errors. If you have connection errors, double check the Apache and MySQL ports in the General tab of MAMP. I personally use 80, 443, and 3306 rather than the default.