I've been fighting through this with the help of the documentation on the site, but keep seeming to hit blocks. I am moving a tiki database to a new server and taking over from the previous administrator. The database is still mysql and tiki 2.0. The database is encoded in Latin1. The database includes a large amount of Japanese text.
Upgrading directly to 12.1 produced errors in the Japanese text encoding, which I believe was due to double encoding errors. I reinstalled the sql file, this time using --default-character-set=latin1 (as recommended by the tiki documentation when having double encoding errors).
Next I upgraded to 3.9, which preserved the Japanese encoding but produced errors in the table encoding for some pages. The 3.9 install does not allow any of the process suggested on the Upgrade page (http://doc.tiki.org/Upgrade#Fix_the_encoding_issue), so I then tried to upgrade to 12.1.
During the step 5 "Convert database and tables to UTF-8" process I had a timeout error. I increased my php.ini max_execution_time to 120 and tried the install again. This time I was not given the "Convert database and tables to UTF-8" option at step 5, but did do the very last step of "Dangerous: Fix double encoding." The installer tells me I am successful.
The end result is a system error page when I try to enter the tiki: "An error occurred while performing the request."
Checking my database in MySQL shows no errors. The database credentials in my local.php file are accurate.
Does anyone have any suggestions on what to do other than restoring the sql file yet again and remaining at tiki 2.0? I would really like to upgrade but seem to be having no luck because of the Japanese text problem.
Thank you for any suggestions!