Upgraded this site's underlying software from Movable Type 2.661 to Movable Type 3.11 today. Following the upgrade instructions got me into trouble straight away simply because I uploaded the required files as the root user instead of from my user account. This gave all my files the wrong owner and group, which caused mt-upgrade30.cgi to give me this error:
Bad ObjectDriver config: Connection error: Access denied for user: 'thoughton@localhost' (Using password: NO)
After poking around a bit, I figured out that simply using the Finder instead of FTP to copy the required files from the MT-3.11-upgrade-en_us folder to my CGI-Executables folder solved this problem. Opening mt-upgrade30.cgi in a browser now produced some upgrading messages. Opening mt-upgrade31.cgi finished the job. Movable Type 3.1 should now be installed! But first I had to iron out a few problems.
The first thing I noticed upon logging into the new MT 3.11 installation was that the screen was all mixed up, with some new background images and some old (version 2.661) background images. Rebuilding the entire site fixed this, but on my first few rebuilds I got permissions errors involving index.html, index.rdf, index.xml, rsd.xml and archives.html files. Using the Finder to change the permissions of these files so that the group owner was 'www' and had read and write access fixed these rebuild errors.
Voila! Logging into the site worked fine now. One of the first things I did was to go to the preferences section and uncheck 'Use Old-Style Archive Links'. This switches the individual archive entries to have meaningful names (like upgrading_to_mo.html instead of 000090.html). Rebuilding after this produced a new permissions error involving MT's local archive path (on this site the path is tim/weblog/). Using the finder to change the ownership of the folder so that it was in the www group with read and write access fixed that problem.
I soon realised that the new site did not have the category icons anymore, but copying over topicon.pl and topicon.cfg from my old MT install followed by a rebuild fixed that! So far everything else seems to be working. Watch this space!
Update: Due to the extra two levels in the directory structure of the new meaningful-name archive files I also had to update some image paths on the archive templates.