How do I solve a 406 error if it's just on one computer?

  • Answered
Hi, it's really strange but on just one computer we are getting this error on our site

Not Acceptable

An appropriate representation of the requested resource / could not be found on this server.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.

On other computers the site works fine and if we clear the cookies on the one computer then the site works fine.. for a while. Then it happens again. But only on this one computer.

So bizarre. Any idea what is causing this because I'm stumped?


It's so bizarre. I completely removed Firefox 10 and then installed Firefox 11 Beta and the problem still occured. So we decided to shift to (spit) IE9 and it worked fine for a while but now it's doing the 406 error on IE9 as well!!

Clearing the cookies makes it work again for 5 to 10 mins then it screws up again with another 406.

The site works fine on our other computers but not this laptop (which is important). All other websites work fine too. Any thoughts on the matter would be great. I'm completely stumped.

Might just reinstall windows if we can't figure it out soon.

(Tested using Firefox 10 and 11 and IE 9.)

--UPDATE 2--

Hi again, I'm now tearing my hair out as the problem has now occured on a second machine. This machine has XP (rather than win7), uses Avast AV (as opposed to MSE on the other) and and Firefox 9.

The machines are unrelated.

The problems seems to occur if I log into the wordpress admin page then go from there to the shop page then click a tab on the shop. As soon as the 406 occurs, no single page works on the domain.

If you could try visiting the shop on

Have a browse and see if you can replicate the error. Now I'm sure it's not the OS or the browser, I doubt trying Chrome or disabling AV would work and to be honest I want it to work cleanly because of course I need to know our future customers will not have the same problem.

Hope this makes some sense?

Thanks so much for your kind attention to this issue.
Tim S.
Hi Liam23, Thanks for giving us the credentials so I could replicate the issue. I'm more than happy to assist you. I've replicated the 406 error and looked into the error logs to determine its cause. The issue is due to Mod_Security. Mod_Security is an added layer of protection we enable on the server to prevent certain types of attacks or hacks. Here's an article explaining Mod_Security in more detail. I dug a little deeper and went into your WordPress dashboard to see if I could determine the exact nature of the error. I turned off all your WordPress plugins and checked the site. At this point there were no errors, thus determining it's one specific plugin causing the problems. I turned on the plugins one-by-one and found the issue is with the Woocommerce plugin. As soon as I activated the plugin the 406 errors returned. I looked online for a solution by did not find any documentation on Woocommerce and Mod_Security.

Solution #1

At this point you can send a request to our support department ([email protected]) and request Mod_Security be turned off for that specific domain. Don't forget to mention the domain name you want mod_security de-activated for if you choose this option. Also, you'll need to verify your account with the last four digits of the credit card or the current AMP password.

Solution #2

You can contact WooThemes (the developer of the plugin) to see if they are aware of a fix so you can use Mod_security and Woocommerce. Here's a link to their public forums: Woocommerce Public Forums I hope this helps! If you need further assistance please feel free to contact us. Thanks! Tim S
Tim S.
Hi Liam23,

Thanks for getting back to me. It's tough to troubleshoot since I cannot replicate the error. Is there anything installed differently on this laptop such as a malware or virus scanner? I've tested it out in FireFix as well as Chrome and cannot replicate the error.

Have you tried installing Google chrome to see if it works in that browser? Also, I'd check any anti-virus software. Disable it for a while and test the website to see if that is causing the issue.

If you need further assistance please feel free to contact us.


Tim S
Tim S.
Hi liam23,

Thanks for posting your question. I'm more than happy to assist you. I've tested the website in the Chrome web browser without any errors. Since you're able to view the site intermittently on the one computer in question, it sounds like an issue with the web browser. Have you tried a different web browser on the same computer? Also, what web browser and version are you using that you are seeing the error.

Basically, a 406 error is saying that the server is sending data to the web browser in question, and the web browser does not like it.

Try using a different web browser and see if the issue still occurrs on the computer and let us know.

If you need further assistance please feel free to contact us.


Tim S