Not everyone follows instructions. When upgrading your WordPress site not following the upgrade instructions can cause some really unpleasant things to happen and give some scary error messages.
Maybe you messed things up through ignorance. Or if you’re like me you might just try doing it wrong just to see what happens.
If you’re in a panic and feeling like the guy to the left here because your upgrade seems to be messing things up, don’t fear. Most problems can be overcome.
And the good new is hopefully you won’t even loose much of your data!
Provided we do things right, that is. 
Putting it Off
I have an old much neglected personal blog that I’ve been hesitating to upgrade. There have been several new versions of WordPress out since I’d last upgraded it. I knew the theme I was using was not compatible with the latest version along with an unknown number of the way too many plugins I was running on the site.
Top that off with the fact that I was using the Ultimate Tag Warrior plugin and was unsure how the conversion would work out now that WordPress has native tagging built in and I’d been really procrastinating.
Yesterday I had at it. Finally.
Wrong Way Upgrading
One thing I did do was backup my database files. Especially after our web hosting discussion, there was no way I was going to intentionally mess things up without a good backup.
Then I intentionally left the theme I already knew was incompatible with the newest version of WordPress active. I left all my plugins active and hit the upgrade link in my web host’s Fantastico module.
Yep. Bad things happened.
The first thing I noticed is that I had data base errors scattered throughout the front of the blog when pulled up the base URL.
Better deactivate that bad theme and the plugins to track down the problem.
So I clicked my bookmark for the WordPress control panel of the site and was greeted with an all white screen with big black letters that said something along the lines of
Fatal error: Call to undefined function get_admin_page_title() in … /wp-admin/admin-header.php on line 12
Ooh! That makes it tricky.
How do you deactivate the plugins and theme that’s causing the problems if you can’t get at your Dashboard?
The answer is easy. You go in through your server.
Move Theme & Plugin Files
The idea is we’ll move the theme files to another directory and “get them out of the way” so that they are no longer interfering with WordPress. Then we can move the folders back one at a time until we find the problem children.
So what I did was log in to my web hosting server. I created a temporary directory on my server. Call it “junk” if you want. Then I moved my theme folder from wp-content/themes into the junk folder.
Doing that fixed most of the errors on the front of my blog. Of course it also reset things to the WordPress default theme. But I still had the same problem and couldn’t access my WP dashboard.
I just went back to my web host file manager, selected all the plugins, and moved them all to the junk folder.
Then I could access my dashboard and keep rolling. All is well!
Important Note
There is one more important step to be sure you do. This falls in the “read the instructions” category.
After you get your new version of WordPress up and running, be sure to tell WordPress that you upgraded by going to http://example.com/wordpress/wp-admin/upgrade.php where “example.com” is your site domain and “/wordpress” is the directory WordPress is intalled in.
If your it is located in the root directory then you will use http://example.com/wp-admin/upgrade.php and you should be good to go.
This step is especially important when upgrading to WordPress 2.3 because there are some new tables WordPress needs to create, especially because of the new tagging functionality built into WP 2.3.
Importing Ultimate Tag Warrior Tags
Speaking of tags, WordPress built in an import function to help those of us out who are/were using Ultimate Tag Warrior.
Simply go to Manage–>Import and click on Ultimate Tag Warrior. Then to import your tags you will just have to click through about 4 or 5 screens. Took me all of about a minute, easy as pie.
And that my friends is how you recover from not following the instructions when upgrading your WordPress blog.
So Chris, why updgade? I avoid software upgrades like the plague.
At some point you have too, but how often does WordPress really need to be upgraded? This is probably a two part answer: For power users and us simple folk.
Steve
http://www.coastaluruguay.com
I avoid updating everything unless is extremely necessary..from hardware to drivers, I know something will go wrong no matter what I do
So I just don’t upgrade my stuff..may be sound like I am lazy, but from experience I’ve learned something always goes wrong when updating
I see that ‘Please update now’ on my wordpress blog everyday, and keep putting it off. I used to have this blogspot blog, and I upgraded from a customized classic template to the new widget one, and lost a lot of customizations, not to mention search rankings. I figure I’m not in the mood for another crisis right now…
If I update my wordpress blog to the newest version, some of my important plugins will not work anymore.If it is not broken, why fix it?
I botched a wordpress upgrade early January and my site was down for about 1 day. The problem? It was a plugin! After deactivating all the plugins and reactivating them one by one, I found the problem.
I have an old much neglected personal blog that I’ve been hesitating to upgrade. There have been several new versions of WordPress out since I’d last upgraded it. I knew the theme I was using was not compatible with the latest version along with an unknown number of the way too many plugins I was running on the site.
You have made me soo happy. I had the same problem with being unable to get into the dashboard because of the plug in error and fixed it in 3 seconds after I read your solution.