Some of my clients have come across something similar to this nasty little error message after updating to WordPress 3.0:
Warning: call_user_func(extract_terms::update_taxonomy_count) [function.call-user-func]: First argument is expected to be a valid callback in .....wp-includes/taxonomy.php on line 2056

Warning: Cannot modify header information - headers already sent by (output started at .../wp-includes/taxonomy.php:2056) in ...../wp-includes/pluggable.php on line 890

After futzing around and asking questions about how they upgraded, I found that none of them deactivated their plugins first.

Just to refresh your memory, here are the basic steps for upgrading using WordPress’s built-in upgrade tool:

1. Back up your database and your wp-contents folder
2. Deactivate all your plugins
3. Upgrade (plugins first, WordPress second)
4. Reactivate your plugins
5. Test

Reactivating your plugins one-by-one and testing (that is, reloading your site and publishing or re-publishing a post) after you activate each one is important, and time consuming. But it’s the first thing I do whenever a WordPress site is throwing scary-looking errors.

If you still have problems, and WordPress is still throwing up errors, try switching to the default theme (in WP 3.0 it’s TwentyTen), and reloading your site. Sometimes themes that haven’t been updated in a while can conflict with some code in a new update.

If you’re still having trouble with your WP 3.0 install and are this close to tossing your computer out the window, put the computer down, take a deep breath, and get in touch with me.

If video embedding has you flummoxed, keep reading…

To embed a video you used to have to copy and paste a big hunk of code in your WordPress post. Crazy, eh?

Well, no more searching for the embed code for your video!

WordPress 3.0 makes use of a dealie (technically a “protocol”) called oEmbed which will automatically transform your simple video link (i.e. http://www.youtube.com/watch?v=rfh4Mhp-a6U) into this:

All you have to do is take the URL (web address) of your video—something you can copy & paste from your web browser address bar—and paste it into your post. Simple!

Now, if you want a bit of control over the size of your video, you can add a little extra code, but it won’t hurt… Making the video 300 pixels wide looks like this:

aaannnd… it looks like this:

This nifty little dealie works with YouTube, Vimeo, Viddler, blip.tv or any number of other video hosting sites. Check out the WordPress codex for a full list.

Now, if you want to make all videos to be 300 pixels wide by default (that is, you don’t even have to do the embed code), go to Settings > Media on your dashboard and under the Embeds area, type in 300 for the width. Make sure you hit the save changes button to save that change. It’ll look a little like this:

So, no more digging and searching and hair-pulling (or crying for that matter) to figure out how to add video to your site!

Welcome to the very first installment of Secure Your WordPress Site Without Bursting into Tears!

In this video we’re going to get rid of the admin account. In versions prior to 3.0, WordPress automatically created a user account named “admin.” Most site owners never change this, so hackers can take advantage of only having to crack the password instead of both the password and the user name.

In version 3.0, during installation you can now specify your very own username.

So now for the video!

Don’t miss the next video! Sign up for the mailing list on the right side of this page to get updates on this series.

And remember… there’s no tears in WordPress.

A lot of bloggers say you shouldn’t write really long articles and to keep your blog posts to about 500 words. But sometimes you just have to let the words flow. To a point. There is such a thing as blog post that’s too long.

For those times where you find yourself pouring out boatloads of information, and you don’t want to overwhelm your reader with the endless scroll, there’s a fancy built-in pagination feature in WordPress.

To use it, at each point you’d like a new page to begin, type in the following:

<!--nextpage-->

You can see it in action at the bottom of this post.

Sure it’s a little tedious if you have an post that spans 20 pages. At that point I’d revise and cut out stuff in order to whip the post into shape for internet consumption.

There are other pagination plugins around the WordPress world, but I’m all for keeping it as simple as possible.

One tragic thing I keep seeing on the web is creators – people who make stuff, tangibles or intangibles – without their own home on the web.

They’re taking up space on Blogger, WordPress.com, Typepad, deviantArt and other places that give ‘em an illusion of having their own home.

Landlords may be nice and kind or rude, sneaky and evil. You never really know what kind that landlord is until you get on their bad side.

I’m not saying that those companies that offer free blogs and web sites and portfolios will turn on you, but do you really want your business at the mercy of the terms & conditions of some other company?

You need to own your own home on the internet.

• The investment isn’t all that bad ($10 for a domain name, $100/yr for decent hosting).
• It’s your brand and your name that’s up at the top instead of Blogger’s.
• It enhances your authority in the eyes of your potential customers and clients.
• It gives you something authentically you to put in the “your web site” area on those portfolio and networking sites.
• You have more flexibility to make the site look and work the way you want to.
• And you are the one who wields the power (barring the restrictions of the less-strict TOS’s of your new web host, but as long as you’re doing business honestly, you have nothing to worry about).

If you have a “home” on the internet that you don’t own, it’s time to reconsider. For your business’s sake.

If you need help deciding on how to go about getting your own home on the internet, please email me. I’m here for ya.

photo credit: vonSchnauzer

It’s WordPress Essentials week at WordPress Guerilla. Over 50 posts on must-have plugins for WordPress. If you ever needed a bit of direction with the hundreds of thousands of plugins out there – this is definitey the series to follow!