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I cannot upgrade version 42.0. Why won't the 44.01 install not replace version 42.0?

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  • Last reply by FredMcD

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I keep getting the separate notification window that there is a new 43.01 version even after I've supposedly installed 44.01 64-bit.

O/S: Win7Pro

After relaunching Firefox after installing the version upgrade (44.01), the 'Help --> About' panel still shows 42.0 and I continue to receive that there is a new version available.

I keep getting the separate notification window that there is a new 43.01 version even after I've supposedly installed 44.01 64-bit. O/S: Win7Pro After relaunching Firefox after installing the version upgrade (44.01), the 'Help --> About' panel still shows 42.0 and I continue to receive that there is a new version available.

Chosen solution

Download Firefox For All languages And Systems {web link} Save the file. Then;

Using your file browser, open the Programs Folder on your computer.

Windows: C:\Program Files C:\Program Files (x86) Mac: Open the "Applications" folder. Linux: Check your user manual.


Look for, and rename any Mozilla or Firefox program folders by adding .old to them.

After rebooting the computer, run a registry scanner. Then run the installer. If all goes well, remove the OLD Firefox program folders when you are done.


edit: added Program word as users would have very easily deleted their Profile(s) if they were to find and delete "any Mozilla or Firefox" folder as suggested.

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All Replies (2)

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I eventually figured out that installing the 64-bit version triggers the 'upgrade' condition in the wizard but does not actually replace the 32bit version.

Upon reviewing processes in memory, I discovered that I had been using the 32bit version and have to stick with the 32bit version even though my Windows machine will support 64bit applications.

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Chosen Solution

Download Firefox For All languages And Systems {web link} Save the file. Then;

Using your file browser, open the Programs Folder on your computer.

Windows: C:\Program Files C:\Program Files (x86) Mac: Open the "Applications" folder. Linux: Check your user manual.


Look for, and rename any Mozilla or Firefox program folders by adding .old to them.

After rebooting the computer, run a registry scanner. Then run the installer. If all goes well, remove the OLD Firefox program folders when you are done.


edit: added Program word as users would have very easily deleted their Profile(s) if they were to find and delete "any Mozilla or Firefox" folder as suggested.

Modified by James