This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Error massage: Update XML File Malformed 200.

  • 5 cavab
  • 56 have this problem
  • 1 view
  • Last reply by wd1314

more options

After downloading Fire 3.4.16, I have received a Error massage: Update XML File Malformed 200. I can only do this question by using Windows Internet Explorer. So my logic says it is Firefox software and not my machine. But what? Yours sincerely Derek

After downloading Fire 3.4.16, I have received a Error massage: Update XML File Malformed 200. I can only do this question by using Windows Internet Explorer. So my logic says it is Firefox software and not my machine. But what? Yours sincerely Derek

Chosen solution

There are a few possible causes for that error, for details see https://support.mozilla.com/kb/AUS+Update+XML+File+Malformed+200

Read this answer in context 👍 2

All Replies (5)

more options

Seçilmiş Həll

There are a few possible causes for that error, for details see https://support.mozilla.com/kb/AUS+Update+XML+File+Malformed+200

more options

No, as I said in my question I have tried AUS Update XML File Malformed 200 to no avail. When I open Firefox the tabs try to open the web sites but I end up with nothing, but the tab is now 'Untitled'. I have rebooted my machine. I have re-downloaded the update.

more options

I too have the same problem. Is there a solution?

I am using an old backup machine to write this as my new machine is useless unless I use IE.

Please help....................


Jay

more options

I have a variation of this problem. FF works fine for about a day then can navigate normally (no freeze or errors) but can not connect to anything. When I check for updates the error occurs. Closing and restating FF does not solve the problem (Operates normally but no connections and same error). A machine reboot restore connectivity and the update checker works again.

OS is Win2K and FF ver is 3.6.16. Believe it happened shortly after the upgrade to current version.

more options

I have tried everything possible and I still get Update XML file malformed (200). What can I do? I tried to uninstall and then re-install and I still get that msg.