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

What does "The download cannot be saved because an unknown error occurred" mean?

  • 3 cavab
  • 2 have this problem
  • 11 views
  • Last reply by You

more options

I've received this message on my computer, "Looks like you're using an older version of Firefox." Free download. Click. When I click, a box appears with this message: "Firefox Setup Stub 35.0 exe. Would you like to save this file?" Options are "save file" or "cancel." When I hit "save file", the message is "The download cannot be saved because an unknown error occurred." Can you help me figure out how to proceed with upgrading Firefox Mozilla? Thank you.

I've received this message on my computer, "Looks like you're using an older version of Firefox." Free download. Click. When I click, a box appears with this message: "Firefox Setup Stub 35.0 exe. Would you like to save this file?" Options are "save file" or "cancel." When I hit "save file", the message is "The download cannot be saved because an unknown error occurred." Can you help me figure out how to proceed with upgrading Firefox Mozilla? Thank you.

All Replies (3)

more options

You can use Internet Explorer to download Firefox. Click the Start button, type Internet Explorer to begin searching for Internet Explorer, and click the first search result to open it. You can then visit https://www.mozilla.org/en-us/firefox/new to download Firefox.

more options

It is possible that anti-virus software is corrupting downloaded files or is interfering otherwise.

Try to disable the real-time (live) scanning of files in your anti-virus software temporarily to see if that makes downloading work.

Try to download the full installer instead of the stub:

Boot the computer in Windows Safe Mode with network support (press F8 on the boot screen) as a test.

more options

Your settings might be corrupt, too, so if Cor-el's suggestions don't work, then reset your settings.