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Running Windows XP, firefox automatically updates, no update since last open, what appears to be a windows error message "Could not find the mozilla run time"

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  • 2 have this problem
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  • Last reply by FredMcD

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Firefox does not start. What appears to be a Windows XP message comes up: "Could not find Mozilla runtime." Firefox automatically updates. No update since last firefox ran earlier in the day. Nothing appears to have changed.

Firefox does not start. What appears to be a Windows XP message comes up: "Could not find Mozilla runtime." Firefox automatically updates. No update since last firefox ran earlier in the day. Nothing appears to have changed.

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Have you tried installing Firefox from a full installer? That might work better. https://www.mozilla.org/en-US/firefox/all/

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The same thing just happened to me on Win 7

I closed firefox. Then I tried to open firefox, a small update style window showed up, with a progress bar, for a second or two. Then it showed an error box "Could not find the mozilla run time", and wouldn't load firefox.

After that, any time I try to launch firefox, all I get is "Could not find the mozilla run time"

I had to use IE to download firefox and install it again to fix this.

I wonder what is up with this? A bug?

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