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Downloaded latest Firefox version but cannot open as say another version is already running even if I do not have it open. What is wrong?

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Downloaded the latest version of Firefox on my Mac and it won't open as keeps saying that Firefox is already running. This keeps happening even after I log out and re-boot the computer. I don't understand why if I do a download to an existing operation it doesn't piggy-back onto the old one and function. Please help as I have looked at all your Q & A and did not find anything to address download won't work because older version still "running" even when closed. I have Mac OS X version 10.6.3. Thank you.

Downloaded the latest version of Firefox on my Mac and it won't open as keeps saying that Firefox is already running. This keeps happening even after I log out and re-boot the computer. I don't understand why if I do a download to an existing operation it doesn't piggy-back onto the old one and function. Please help as I have looked at all your Q & A and did not find anything to address download won't work because older version still "running" even when closed. I have Mac OS X version 10.6.3. Thank you.

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Try this:

  1. Open Firefox (or another Browser) up.
  2. Go to www.getfirefox.com
  3. Download the Firefox installer to your computer, and save it somewhere you will remember
  4. Restart your PC
  5. Install the new version of Firefox you downloaded (How to download and install Firefox on Mac)
  6. Restart your PC one more time, then Fire up Firefox

Hopefully it will work now and you should be all updated.

Bewurke troch user633449 op

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Create a new profile as a test to check if your current profile is causing the problems.

See "Basic Troubleshooting: Make a new profile":

There may be extensions and plugins installed by default in a new profile, so check that in "Tools > Add-ons > Extensions & Plugins" in case there are still problems.

If the new profile works then you can transfer some files from the old profile to that new profile, but be careful not to copy corrupted files.

See: