Well… mixed results. Replacing the 1.2.8 files with those from 1.5.6 blanked everything, including wp-admin. I tried putting them both in the plugins directory, de-activated 1.2.8, then tried to activate 1.5.6 but it wouldn’t activate.
So essentially the upgrade so far has been a failure. On the other hand it is, as I mentioned, a temporary measure so that isn’t a catastrophe. In the process, though, I discovered that the files we’d been sent originally had been on a mac at some point, and the file system was littered [sic] with mac resource forks. I used ‘find’ to delete those, and we seem to be in a much, much better state than previously! Apparently WordPress tries to load and execute the resource forks where they’re present.
There are still egregious problems with the site, but I’m inclined to think that most of them are to do with the corruption in the db data we were given initially, e.g. existing comments seem to have become disassociated from their original posts, whereas new comments are working properly.
Thanks very much, everyone, for your help. I’m not marking this as resolved since my original problem hasn’t been solved, but I think we’re probably going to leave BuddyPress alone for the moment. WordPress is great when it works, but I’ve found it pretty opaque to debug; thanks again for helping me out!
Thanks everyone! I don’t have a convenient test environment available, but I have backed up the entire database and all the files, so I think I’ll cross my fingers and try stwc’s method, as the easiest – assuming it works!
If it doesn’t then I’ll revert and we’ll try a different approach. Ultimately we’re planning to move all the functionality off the WordPress installation and onto our own system anyway, so there’s a limit to the amount of time I want to put into making it work properly.
Trouble is, when we de-activate plugins, the entire site goes blank – including the admin pages! At least, it’s happened that way before and it was a MySQL nightmare getting it back to normal. We never managed to work out exactly what plugins were causing it to fail when they were de-activated.
I’ll give it a go, though, if I can’t find any other way round it.
