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Why do i keep getting an Alert message saying "The URL is not valid and cannot be loaded "?

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I keep getting an Alert message saying "The URL is not valid and cannot be loaded " when i try to load a page using Mozilla Firefox and i have to click OK. I have to keep reloading the page.

Operating system

Windows XP

I keep getting an Alert message saying "The URL is not valid and cannot be loaded " when i try to load a page using Mozilla Firefox and i have to click OK. I have to keep reloading the page. == Operating system == Windows XP

All Replies (4)

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Does this happen with every page, or specific ones? Do you have a URL we can test?

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Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of your add-ons is causing your problem (switch to the DEFAULT theme: Tools > Add-ons > Themes). See Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems and Troubleshoot issues with plugins like Flash or Java to fix common Firefox problems

If it does work in Safe-mode then disable all your extensions and then try to find which is causing it by enabling one at a time until the problem reappears. You can use "Disable all add-ons" on the Safe mode start window. You have to close and restart Firefox after each change via "File > Exit" (on Mac: "Firefox > Quit")

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I happens with just about every page i try to load especially Facebook and Gmail.

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How can this problem be solved?