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Why does Firefox cause much slower up/download speed results using speedtest.net versus Explorer?

  • 3 replies
  • 1 has this problem
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  • Last reply by cor-el

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I pay for 300mps download and 20mps upload speeds from my internet service provider. When I test internet speeds via www.speedtest.net on Explorer, the results are consistently in line with these. When the same speed test is run on Firefox, the results are much much slower on the download (>50mps) and about the same on download (20mps). Why??

Also, I find that Firefox crashes from time to time and is slow to load pages.

I've disabled hardware acceleration, emptied cache and my plug-ins are up to date.

What do I have to do to stop this?! I'd like to continue to use Firefox as my default browser but this is becoming a real challenge.

I pay for 300mps download and 20mps upload speeds from my internet service provider. When I test internet speeds via www.speedtest.net on Explorer, the results are consistently in line with these. When the same speed test is run on Firefox, the results are much much slower on the download (>50mps) and about the same on download (20mps). Why?? Also, I find that Firefox crashes from time to time and is slow to load pages. I've disabled hardware acceleration, emptied cache and my plug-ins are up to date. What do I have to do to stop this?! I'd like to continue to use Firefox as my default browser but this is becoming a real challenge.

All Replies (3)

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hello, when you are using speedtest.net or a similar flash-based site to measure your connection speed, it might be an issue with the protected mode that adobe has introduced for its flash plugin for firefox. some old versions of f-secure or trusteer rapport are known to cause such slowdowns together with flash, or it might be something similar on your system that is interfering (maybe security software that is blocking/sandboxing the container used for the protected mode, etc...).

as a workaround you could try disabling protected mode & see if this makes a difference...

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Hi Philipp Thanks for your feedback. I have the latest version of Adobe Flash - adobe 16,0,0,305 as well as the latest version of Firefox and Norton 360.

I checked the link http://forums.adobe.com/thread/1018071#TemporaryWorkaround to disable protected mode but I don't feel comfortable with changing the mms.cfg file.