WordPress Flash Uploader Fix for the HTTP Error
Last week I mentioned that I was having problems with comment moderation since upgrading to WordPress 2.7. Well, I was also having trouble with the flash uploader. I would get an error and have to use the browser uploader. Not a big deal but it annoyed me and slowed me done because I could only upload one image at a time.
So, I also decided to tackle this when I did my WordPress spring cleaning and I found a solution that worked for me.
When I would try to use the flash uploader for images I would get an error that said HTTP Error in bright red and nothing would happen.
When I started doing some research on the WordPress forums I discovered that there were many causes of this problem and just as many possible solutions. My heart sank a little because I wanted one simple answer and didn’t want to try a lot of different solutions. I am, however, only going to discuss the solution that worked for me.
The error is often caused by mod_security, which is a security module installed by the web host. This can be corrected by modifying the .htaccess file and there are two ways to deal with this.
- Install the Image Upload HTTP Error Fix plugin. The plugin adds the necessary lines to the .htaccess file. I have not tried this plugin so can’t vouch for it but people seem to be using is successfully.
- Edit your .htaccess file. This file is at the root level of your WordPress installation. Download it via ftp, make a copy, and then add the following lines to it.
#BEGIN Image Upload HTTP Error Fix
<IfModule mod_security.c>
<Files async-upload.php>
SecFilterEngine Off
SecFilterScanPOST Off
</Files>
</IfModule>
#END Image Upload HTTP Error FixThen upload the edited .htaccess back to the root level of your WordPress installation.
I used the second solution because I am familiar with editing the .htaccess file and didn’t want to install another plugin just to do this for me. If you are having a similar problem with the flash uploader this solution may correct it. This thread in the WordPress forums discusses other possible solutions if this one doesn’t work for you.
photo credit: Ray Radlein
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April 6, 2009 at 3:59 am
Plugin route may be easier for dummies though you never know the outcome of the plugin. I had some weird plugins in the past that updates robot.txt but I would back it up first, cross check it three four times before allowing the changes.
Editing directly is a better approach like you and I would do (though I am not that good in .ht configurations). Backing up is a step that one should always remember :)
Ajith Edassery´s last blog post – T3Leads review – An affiliate program that is exciting
April 6, 2009 at 2:29 pm
Hi Ajith – I just copied and pasted it into my .htaccess file. But I did back it up first – I’ve made mistakes with it in the past, which made my site inaccessible.
April 6, 2009 at 8:23 pm
I was just about to make a “ATTENTION NEWBIES” comment in regards to being very careful with the .htaccess.
Awesome savable tips though, thanks. :)
Dennis Edell´s last blog post – 9 Qualities You Should Find In A Good Web Designer
April 6, 2009 at 11:42 am
Reading the code over, it makes total sense.
For the unfamiliar, it’s overriding a server security setting. In other words, it’s not WP or Flash that’s the problem – it’s the server.
Andrea_R´s last blog post – Two things
April 6, 2009 at 2:30 pm
Hi Andrea – See, that’s why I said you are smart :-) I should clarify that it’s the server causing the error rather than WordPress.
April 6, 2009 at 8:24 pm
Then shouldn’t one contact the host regarding it?
Dennis Edell´s last blog post – 9 Qualities You Should Find In A Good Web Designer
April 7, 2009 at 7:22 pm
You could try – some hosts incorrectly think they need mod_security.
April 6, 2009 at 3:06 pm
I would like credit for reading this, even though I am not sure exactly what was said.
Although seriously, the more I just read these kinds of posts from you the more little bits of knowledge I am getting, so thanks so much! When I first started, I didn’t know what a php was! I still don’t precisely but I’m getting a vague idea. That’s progress!
Tracy´s last blog post – 6 Things I secretly hope are included in life coaching
April 6, 2009 at 4:04 pm
Hi Tracy – I guess it would make more sense if you had ever had the error – so you’re lucky :-)
If some of articles are difficult to follow you can also enjoy the photos at the top – I was especially happy with my find for today.
April 6, 2009 at 4:40 pm
Sweet; I’ve had issues with the flash uploader for a while now; will give this a shot.
Donace | The Nexus´s last blog post – Traffic Android Review
April 7, 2009 at 7:23 pm
Let me know if it solves the problem for you – there is more than once cause and solution for flash uploader problems.
April 8, 2009 at 3:58 pm
I need to get the anti-spam thing, about 95% of comments needing moderation are those. Jeez Louize, get a life people — no one needs your viagra and online slots already.
LOVE the pic you chose for this.
Jannie Funster´s last blog post – Potential Regalements
April 8, 2009 at 6:55 pm
Hi Jannie – Do you use Askimet? It’s not the only anti-spam plugin but it does work really well. And seriously, I think everyone who wants viagra has already purchased it. And the spammers are SO sexist – all their spam is targeted at men ;-)
Thanks for mentioning the photo – I was really proud of that find.
April 13, 2009 at 10:30 am
I am also facing a problem with the Flash Uploader. When i click on “Choose Files to Upload” , nothing happens while the browser uploader works fine. Any idea what could be the problem ?
Madhur Kapoor´s last blog post – Read It Later Firefox Extension
April 13, 2009 at 11:49 am
Hi Madhur – Unfortunately, there are so many reasons why the flash uploader might not be working.
In this thread, Otto lists all the main reasons and things to try
http://wordpress.org/support/topic/164999
Also, have you tried in both IE and Firefox?
April 19, 2009 at 1:15 pm
Thanks for the link. Happening in both IE and FF. i think the problem can be in flash player
Madhur Kapoor´s last blog post – Change Desktop Wallpaper Periodically with ThetaWall
April 20, 2009 at 6:33 am
Hi Madhur – Well, at least that eliminates the browser. Have you tried using a different computer? That might give you more information. And maybe something on that list will help.
July 29, 2009 at 12:18 am
Thanks for this post.
It work for me.
.-= Hoi An´s last blog ..Hội An: Giới thiệu tiềm năng du lịch trên mạng =-.
July 29, 2009 at 8:06 am
Hi Hoi – Great! I’m glad it fixed the problem.
January 20, 2010 at 9:27 am
Just chiming in to say it worked for me. Cheers.
January 20, 2010 at 2:05 pm
Hi Nils – Great! Thanks for letting me know.
February 21, 2010 at 6:37 am
hey there – it worked for me as well. cheers!
February 21, 2010 at 12:13 pm
Hi Steph – Great! I’m glad it solved the problem.
May 2, 2010 at 7:14 pm
Hi –
Thanks for your post. I have been using the flashuploader without any problem for a while. Suddenly it stops working and I cannot find the solution, despite trying many different “solutions”. ARGGHH!
Now when I upload an image using the flashuploader, i just get the little red HTTP Error – and that’s it. And only in Firefox – IE works fine – curious eh?
I also have another WordPress site, but there’s no problem with that one, so I figure “it must be something in this site”.
So, I disabled all of my plugins – still no joy.
Checked that Firefox was up to date – all good.
Then I uploaded the .htaccess file – nope!
Changed all of my setting back to default – nope.
Contacted my webhost, gave them a username and password so they can recreate the problem and I’m hoping to get an answer back today….
If that doesn’t work, I am facing the prospect of re-uploading my entire site and starting again…… if I decide I can’t live with the manual upload!
Although It’s a not a biggie – it is sure annoying. WordPress is so great, but it does amaze me that these “erroneous” problems can come up that steal your time.
I’ll keep you updated :-0
May 2, 2010 at 8:39 pm
Hi Sol – If nothing else has changed, it is most likely that something changed with your host.
Did you update Firefox or add a new Firefox add-on?
May 2, 2010 at 11:04 pm
Hi Kim
My host says they cannot replicate the issue. It must be Firefox playing silly devils with me…. but as I say, works fine with my other site!
I’ve cleared my cache and cookies a half a dozen times, checked I’ve got the latest browser version (I do) and update Flash Player too…. still no luck!
How maddening – and how curious…. Will post an update if I ever get to the bottom of it….
May 3, 2010 at 7:23 am
Hi Sol – Have you tried disabling your Firefox add-ons to see if that helps. At this point that sounds like the most likely culprit.
June 23, 2010 at 3:03 pm
The weirdest thing happened to me, I use ubuntu and I’d never had this issue before, until a friend of mine tried to upload images using Windows (we tried different browsers)
This fix sure worked for my pal, the true mistery here its: why it’s an issue only in Windows based browsers?
Cheers
.-= Chuck´s last blog ..davidmh: @pancitaict no sabia que tenia otro hermano :/ =-.
June 24, 2010 at 7:17 am
Hi Chuck – I’m glad the fix helped your friend. That’s odd that it’s a problem for Windows – since the fix is added to the .htaccess that doesn’t make sense logically.
June 24, 2010 at 10:54 am
Hi Kim,
The more I think about it, the less sense it makes.
I just made another test in a site without this fix, using both windows and linux, and again the error only happen in windows.
Look: http://i50.tinypic.com/6h8awl.jpg
June 24, 2010 at 10:29 pm
It’s one of those things … I’m scratching my head over it.
August 30, 2010 at 4:33 pm
Just got my HTTP error resolved.
Editing htaccess did not help, so I contacted my hoster. They whitelisted the WP/Flash upload so it would not trigger the mod_security rules anymore.
Hope this helps someone else because I spent hours trying out differnet solutions.
August 30, 2010 at 5:58 pm
Hi Zudie – Sometimes asking the host about the problem is the best solution – I’m glad it got resolved.
February 1, 2011 at 1:53 pm
Thank you, worked great!
April 27, 2011 at 1:14 pm
Unfortunately, this did not work for me on WordPress 3.1.2.
April 29, 2011 at 4:11 pm
It doesn’t fix it for all issues with this but it is one fix – the article is older now and I haven’t tested it with new versions of WordPress.
April 29, 2011 at 7:57 pm
It worked on a new install of WordPress 3.1.2 for me. Thank you!
May 2, 2011 at 12:41 pm
Hi Rob – Great! I’m glad it worked.
June 20, 2011 at 4:56 am
thanks! this helped me on a WP site I am making (new install of WP 3.1.3)
June 20, 2011 at 2:39 pm
Great! I’m glad it helped.
June 25, 2011 at 5:27 am
I found deactivating the smush.it plugin solved all my problems…
Hans Oorschot´s last post ..Jon Horton Personal Trainer: Fotoshoot en website
June 30, 2011 at 3:09 pm
Interesting – there are a number of causes for the uploader error which can make it difficult to troubleshoot.
November 16, 2011 at 1:16 pm
WOW. I’ve been plagued with this issue so long, and this fix took me all of 30 seconds to implement and it worked exactly as advertised.
I love you.
November 22, 2011 at 7:27 am
I’m glad it worked! It doesn’t always fix the problem but sometimes it does.