MAMP Downgrading from version 5 back to 4 and getting error on start

Question

Receiving an error trying to load up MAMP 4.5 after downgrading from version 5 to 4.5 because their serial number system is broke and no one in support is working.

This message comes up when trying to start, any thoughts?

Downloaded from the website under "older versions"

https://www.mamp.info/en/downloads/older-versions/

OS: Mac

Answer 1

I had to downgrade, as well; though in my case it's because mySQL will not upgrade my databases, but I was able to license it.

I was able to successfully downgrade by doing the following:

1. Backed up the /Applications/MAMP folder (just in case)
2. Deleted /Applications/MAMP and /Applications/MAMP Pro.app by moving them to the trash (these were created by MAMP Pro 5 installer)
3. Downloaded and installed MAMP Pro 4.5 from the link you posted above

I'm back up and running with MAMP Pro 4.5 at this point, so looks like everything worked out. Good luck! Depending on your setup, you might need to migrate stuff out of the /Applications/MAMP folder (definitely back that sucker up before you delete it).

Please note: For my original answer, I mis-read the MAMP Pro docs and incorrectly re-located the database directory in /Applications/MAMP/db to my user Library folder (~/Library). This apparently did nothing, because the databases were actually located in the root-level /Library folder. I highly recommend backing this folder up prior to upgrading or downgrading. The MAMP 5 installer automatically copies your mysql56 folder, but the problem I ran into is that evidently it didn't copy all of the database folders within it (which is presumably why the mySQL 5.7 upgrade logic was failing hard on my end). So a backup is a great idea, because the steps the MAMP installer takes to keep a historical backup don't actually work too well in my experience.