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

Firefox Will not install.

  • 3 cavab
  • 2 have this problem
  • 1 view
  • Last reply by Djinbu

more options

Installed update, after which Firefox would no longer open. At all. It would start a process, but the software would not open, and I could not kill it at all through Task Manager. Restarted. Same issue. Uninstalled, rebooted, tries to reinstall. Now your installer won't do anything. Just keeps running with no change.

Windows 10 Home, 64-bit. Not pirated.

Have uninstalled; deleted all Mozilla folders on computer. Then did a stand-alone install. Same issue with Mozilla opening a process, but not the software. Trying to kill the process does not succeed. Using Windows Process Explorer to kill the process results in "Access Denied" even while running as administrator - the ONLY administrator on the computer. I'm guessing the process has tied up resources so it can't be killed.

Have verified the integrity of Windows system files through SFC.

Installed update, after which Firefox would no longer open. At all. It would start a process, but the software would not open, and I could not kill it at all through Task Manager. Restarted. Same issue. Uninstalled, rebooted, tries to reinstall. Now your installer won't do anything. Just keeps running with no change. Windows 10 Home, 64-bit. Not pirated. Have uninstalled; deleted all Mozilla folders on computer. Then did a stand-alone install. Same issue with Mozilla opening a process, but not the software. Trying to kill the process does not succeed. Using Windows Process Explorer to kill the process results in "Access Denied" even while running as administrator - the ONLY administrator on the computer. I'm guessing the process has tied up resources so it can't be killed. Have verified the integrity of Windows system files through SFC.

Modified by Djinbu

All Replies (3)

more options

Please get a Full Version Installer from here : https://www.mozilla.org/en-US/firefox/all/ There may be a issue with the Stub Installer.

Before installing delete any left overs in C:\ Program Files and Program Data and in C:\Users

Please let us know if this solved your issue or if need further assistance.

more options

That's a big no-go. Deleted everything out of app data as well, reinstalled, and still have the same issue.

more options

Djinbu said

That's a big no-go. Deleted everything out of app data as well, reinstalled, and still have the same issue.

To clarify, this time it installed, but now I'm back to the problem of Firefox merely creating a process, but not opening the software. It did, in fact, install.

Update: Ran FSC and it found an error in Windows files. Has been remedied and checked again with no errors. Still having the same problem.

Modified by Djinbu