This document will try to summarize how to upgrade your Mojo Mail installation. If you're using a version lower than 2.4, these instructions should still work for you.
Your old lists should still work! Yes, you may thank me now. They should work because your list settings, archives and subscription list itself is saved wherever you set the $FILES variable (and friends). That means, all you have to do, is install the new version, and make sure you set the $FILES variable the same. If you are using an outside config file, you will only have to make sure you set the $MOJO_CONFIG_DIR variable the same.
Something may go wrong, you back up everything on your computer religiously anyways right? So, before you begin, backup.
=over
I do this anyways, because I feel I'm in total control over everything if there are copies of the files physically on my computer.
cp -R mojo_lists backup_mojo_lists_if_i_makey_a_booboo
tar -zcvf mojo_lists mojo_backup.tar.gz
This takes some prior thought, but it's best to keep the old version around until you see that everything is running just chipper. Yes!, two different versions of Mojo Mail can work on the same lists without anything blowing up really good. This means that you should rename the old mojo directory, the one that's in your cgi-bin. This also means that you have to change the $MOJO_URL variable in the Config.pm file to point to where mojo.cgi is now.
mv -R mojo mojo2_5_1
works well. That way, when you do install the new version and everything checks out, you can just remove the old versionm or just change it's permissions to not to be executable. Just changing the permissions may be a good idea, since an unknown bug may get in your way, that wasn't an issue in the previous version.
If you're reading this, you're also swearing at something as well, eh? heh...
To salvage your list subscribers (you did make that backup, using one of the three ways mentioned above, correct?) just open up every file in your backup that ends in '.list' such as, listname.list 'listname' would be the name of the list they were on. This file holds probably the most important part of your list, the subscribers; so all, is not lost.
Note Mojo Mail was never intended to be moved across servers. You may have complications if you find yourself in that situation. It's possible that the new server will be using a different DB package and downloading/uploading the list setting files in Mojo Mail will corrupt these files.
If you are moving, the simpliest thing to do before moving any Mojo files is to actually compress them, before you transfer them to your new server. Compressing the files may save them from corruption.