My first WordPress upgrade was not fun

WordPress 2.0.6 is out. They say it’s a critical update, so I downloaded it and carefully followed the instructions to upgrade (which can be summed up as backup, backup, backup, upload).

I dutifully backed everything up, ran upgrade.php and got:

Warning: main(/home/1971/domains/

advanced-cache.php) [function.main]: failed to open stream: No such file or directory in /home/1971/domains/ on line 69

Dang. Dang. Dang.

I tried re-uploading the files. No go.


A search found this page which explains how to remove a bad symlink file to fix the problem. I followed those directions, but that didn’t work because I didn’t actually have the advanced-cache.php file to remove.

So back to Google and a search for “wp-cache upgrade advanced-cache.php no such file” found the answer at last, and it was so simple that I could scream at the hour I wasted deleting, re-uploading, and ssh’ing:

in wp-config.php, it looks like the plug in adds the line:

define(‘WP_CACHE’, true);

Delete that line, save, upgrade goes perfectly.


It will be easier next time.


7 responses to “My first WordPress upgrade was not fun”

  1. Funny, I’ve never had to do anything like that. You need to turn that line on, of course, to have a cache and the standard WordPress install doesn’t include “wp-config.php” – it does include “wp-config-sample.php” of course.

  2. I know. I put the file back and everything seems to be okay. Not sure if the cache is actually working, but it shows enabled on the plugins page and it’s listing files. I’m just happy everything is working again.

    The upgrade instructions say not to delete wp-config.php, so I didn’t. So it still had the old file with that line.

  3. Maybe it’s just me, maybe I just don’t like following instructions but after every patch release, I only update the files that have changed since the last patch. The patch process seems really convoluted and overly complicated and unless there is a database structure change, you only really need the changed source files to upgrade successfully.

    But again, I don’t follow most instructions 🙂

  4. Is there a list somewhere in WP-land of those files, Jeffrey? That certainly would have made the process a little easier. Part of the problem for me is that I’m still so new to WP…once I spend more time in it and I feel more comfortable I’ll be able to buck the instructions. 😉

  5. Well, I consider myself lucky. I too just upgraded to 2.0.6. It went pretty smoothly except I have this problem reading instructions. The instructions said DON’T delete this file and that file, but that didn’t seem to stop me from doing it anyway. Thank goodness for backup files. I’m already suffering a bit of anxiety for the release of 2.1

  6. […] On the one hand, upgrading WordPress can be a PITA. I learned that already. To do it right, you have to backup everything (not a big deal since I do that regularly anyway), disable all plugins, delete existing files, upload new files, run upgrade script, re-activate and test all plugins. […]