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When I upgraded to the new Firefox, I'm getting an error message "Invalid URL" on some websites. How do I fix this? I tried searching, but what I found wanted me to change my anti-virus software setting. I'm not running an anti-virus.

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  • Last reply by cor-el

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I have a Macbook Pro that is running OS X. These websites will load on other computers with OS X running the previous version of Firefox.

I have a Macbook Pro that is running OS X. These websites will load on other computers with OS X running the previous version of Firefox.

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Clear the cache and the cookies from sites that cause problems.

"Clear the Cache":

  • Firefox > Preferences > Advanced > Network > Offline Storage (Cache): "Clear Now"

"Remove the Cookies" from sites causing problems:

  • Firefox > Preferences > Privacy > Cookies: "Show Cookies"