Gizmo, I tried going from 6.2 to 6.5.5 but the update.php doesn't work. The install does, but the update.php just comes up blank.
I'd be really interested in seeing what your server error logs display when upgrade.php is called...
I also tried classic (6.7) but that seems really unfamiliar to me. I will have to look into that more. Update: It looks like there's an update package that used to be available to update to 6.7 classic, but it's not available anymore. Am I missing something?
Well, if you're running threads, classic isn't really going to help you; and if you're trying to import into classic, you really should be within v6.5.x of threads to do so (and in that case I'd advise you just to go to Threads v7 from there vs going to classic).
Ruben, the idea is that I am on an older version of CentOS and PHP, that I will update UBB to 6.5 of 6.7, then update/import to 7.2, migrate that to an up to date box, and then update to the newest version. Then I can move the files and DB into production. It's a lot of work but it's the archives for this group.
If they're interested in advanced (non-ubb) support (and have the funding to do so) I've got the time to download their db, do an upgrade off server, and provide them with a v7 set of files (with an updated db); you can find more information
here.