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What have I got installed to block advertisements - I cannot trace anything!

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  • 6 have this problem
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  • Last reply by FredMcD

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On accessing several clean and (to me) respectable websites, I get messages saying that the ad blocking that is in force prevents the site functioning fully and correctly. I cannot trace any installed plugin or add-on that might do this so I presume it is a (hidden) option in Firefox.

How can I find out what is actually doing the blocking and disable it for my selected sites?

I am running version 43.0.4 of Firefox under Windows 7 Pro x64.

On accessing several clean and (to me) respectable websites, I get messages saying that the ad blocking that is in force prevents the site functioning fully and correctly. I cannot trace any installed plugin or add-on that might do this so I presume it is a (hidden) option in Firefox. How can I find out what is actually doing the blocking and disable it for my selected sites? I am running version 43.0.4 of Firefox under Windows 7 Pro x64.

All Replies (3)

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Hello Hershmab,

try to remove the next add-ons you have and see if that helps : Block site, Dangerous Websites Blocker.

go from 3-bar menu on your right-up > Add-ons > Extensions > find it and remove it.

thank you

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Start Firefox in Safe Mode to check if one of the extensions (3-bar Menu button/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem.

  • Switch to the DEFAULT theme: 3-bar Menu button/Tools > Add-ons > Appearance
  • Do NOT click the Reset button on the Safe Mode start window

Create a new profile as a test to check if your current profile is causing the problem.

See "Creating a profile":

If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over problems.

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Hershmab said

How can I find out what is actually doing the blocking

Your System Details shows;

Block site 1.1.8.1-signed ({dd3d7613-0246-469d-bc65-2a3cc1668adc})

Dangerous Websites Blocker 4.5.1.379


Also, other users have made the same complaint; warning, but no blockers.