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Clicking options gives me a page saying "address isn't valid", why?

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  • 1 has this problem
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  • Last reply by FredMcD

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      • It's asked on here already, but the one answer doesn't tell me why OR how to fix it.***

Every time I open FF, I get a dialog box that says Firefox isn't my default browser. I've disabled IE completely. I have no other internet program on my Windows 7 laptop.

Also, Going to "Tools", "Options", I get a page saying "address isn't valid". Also, entering "about:preferences#general<enter>" or "about:preferences#general" or "about:preferences" into the address bar gets me "address isn't valid" as well.

Any Ideas?

***It's asked on here already, but the one answer doesn't tell me why OR how to fix it.*** Every time I open FF, I get a dialog box that says Firefox isn't my default browser. I've disabled IE completely. I have no other internet program on my Windows 7 laptop. Also, Going to "Tools", "Options", I get a page saying "address isn't valid". Also, entering "about:preferences#general<enter>" or "about:preferences#general" or "about:preferences" into the address bar gets me "address isn't valid" as well. Any Ideas?

Modified by Saiyuki53

All Replies (1)

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Let’s do a full clean re-install; Download Firefox For All languages And Systems {web link} Save the file. Then Close Firefox.

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

Windows: C:\Program Files C:\Program Files (x86) Mac: Open the "Applications" folder.
https://support.mozilla.org/en-US/kb/how-download-and-install-firefox-mac Linux: Check your user manual.

Do Not remove the profiles folder.

Look for, and rename any Mozilla or Firefox program folders by adding .old to them. Do not rename the Mozilla Thunderbird folder.

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


If there is a problem, start your Computer in safe mode and try again.

Starting The Computer In Safe Mode;
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