Blocking old versions of Silverlight on Mac OS X

Old versions of the Silverlight plugin for Mac OS X have been added to the Firefox add-on blocklist. We did this because these versions of the plugin are causing instability in Firefox, including crashing on popular sites such as Hotmail.

The affected versions – all versions older than 5.1.0 – will be disabled. To avoid the block, we recommend that you visit the Silverlight page and update your Silverlight plugin to the latest version. If you are unable to update it, or for some reason you need to use the a blocked version of the plugin, it can be enabled again in the Add-ons Manager, in the Plugins pane.

30 responses

  1. E wrote on :

    FYI: I downloaded the latest version of Silverlight (5.1.10411.0); I installed it and restarted Firefox, but Silverlight remained blocked until I enabled it using the Add-ons/Plugin page.

    Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:14.0) Gecko/20100101 Firefox/14.0.1

  2. gorm wrote on :

    I downloaded the most recent version of Silverlight, and it does not even show in the plugin panel. I have deleted the plugin, reinstalled and restarted firefox, and although I can find the plugin in my library, I have no access to it in Firefox. As far as I can tell, there is no way to simply “enable” the plugin, as it is not recognized within the add-ons manager at all. I use it to stream Netflix, and up until last night everything was working fine. What happened here?

    1. Jorge Villalobos wrote on :

      Even when disabled, plugins should show up in the Plugins page in the Add-ons Manager. Make sure that you are selecting the Plugins pane (you should see other plugins like Flash and Java on that list). If you still don’t see Silverlight there, I would recommend doing this: (1) close Firefox, (2) find your profile folder, (3) delete pluginreg.dat, (4) start Firefox. Deleting this file is safe. Firefox will rebuild it out of the plugins in your system when it starts in step 4.

      1. laurel wrote on :

        Brilliant! Thank you Jorge, such a help!

        I couldn’t run netflix, and steps 1-4 solved my problem.

        (1) close Firefox, (2) find your profile folder, (3) delete pluginreg.dat, (4) start Firefox. Deleting this file is safe. Firefox will rebuild it out of the plugins in your system when it starts in step 4.

        1. Laura wrote on :

          Thank you so much! This helped me and now I am able to watch Netflix. I had tried to download Silverlight several times and it wouldn’t show up. This did the trick!

      2. Star wrote on :

        where is my profile folder?
        I’ve been working on this for days. Trying to get Silverlight working.

        1. Jorge Villalobos wrote on :

          There’s a link in my previous comment where you should find an explanation on how to find your profile folder:

  3. Tony wrote on :

    I have a macbook pro version 10.5.8 and Firefox 15.0.1

    My problem is the following. I cannot stream netflix with Firefox, and when I download Silverlight netflix does not recognize that it is already downloading and perpetually asks for me to download it. I spoke to netflix and they said it was a plugin problem, but admittedly I am not entirely computer facile or literate, and have been unable to figure out how to fix the problem. I would be grateful if you could advise and direct me to do this in easy and clearly understood steps if in fact this it the recognized problem. Have a nice day.

    1. Jorge Villalobos wrote on :

      You might be able to get help from our support site. To me it seems like you should be able to go to the Silverlight page and download and install the plugin from there, but I don’t know if there’s something else causing problems for you.

      1. ouida wrote on :

        How can multi- billion dollar companies have such a glaring problem!? fix this shit!!

        1. Jorge Villalobos wrote on :

          Mozilla is not a multi-billion dollar company. Are you referring to Microsoft, maybe?

          What exactly is the problem you’re having?

          1. David wrote on :

            this is not just a problem on Mozilla it is also a problem with Safari

    2. Candide wrote on :

      Update via:

      It seems the microsoft silvelight 5.1 download is actually spitting out the blocked 5.0 version. Go figure! After much troubleshooting, this aabove link resolved my firefox streaming issue.

  4. Donnie wrote on :

    Can not install Silverlight because there’s already a newer version of the program on the disc!
    I already tried with previous advice that you have given the others with no results!

    Can you help me?

    / Donnie

    1. Jorge Villalobos wrote on :

      You have a version of Silverlight that is blocked, and you are unable to update it? Do you have more than one version installed?

      1. Pjottr wrote on :

        I have the lastest Silverlight installed and the plugin is very much enabled
        I run Mozilla FF vs 18.o but I still cannot see streaming videos
        IE 9 and Chrome no Problem
        Pls assist

  5. waseem wrote on :

    Thanks. My silver light plugin was not working with firefox 17, OS X 10.6.8, Now I found one must check after installation if it is enabled or not.

  6. emmett wrote on :

    hello there,

    i’ve installed the silverlight plugin (newest version) and enabled it in firefox, restarted, and firefox seems to keep disabling the plugin. if i try to run netflix, either before or after a reboot of firefox, it asks me to install silverlight again. add-ons manager shows it as the newest version too. curious what i need to do to get this to work. didn’t have an issue with netflix a few months back; this is new.

    thanks for any help.


    1. Jorge Villalobos wrote on :

      Are you on Mac OS or Windows? Which version of the OS?

      1. emmett wrote on :

        hello jorge,

        thanks for the reply.
        i’m on mac OS 10.6.8


        1. Jorge Villalobos wrote on :

          Try enabling the plugin manually. Go to the Add-ons Manager (Tools > Add-ons), select the Plugins pane and look for the Silverlight plugin entry.

  7. David wrote on :

    Mac osx 10.8.2

    1. David wrote on :

      for what its worth I just got it working in Safari Netflix that is. Thank you for your time, I will work with Firefox another time

  8. Mark wrote on :

    I Have Mac 10.5.8 and I have an older firefox version. I want to watch Netflicks and i was watching US netflicks in canada but i closed my internet and started uo again and did not have Netflicks US, how can i do this? O tried Hola and tried to load Hola unblocker for firefox, but it says my version of firefox is not able to do it. I don’t know how i did it before. Can you help?

  9. HC wrote on :

    Cannot get Firefox to even see Silverlight plug in.

    After much research, phone calls with Netflix, etc, still nothing.

    I have downloaded latest version and have also performed the steps you outlined above and still no joy.

    Safari see and works with Silverlight no problem. any other solutions you can suggest before I leave the ‘fox.

  10. HA wrote on :

    I have the same problem and did everything as suggested and like HC I am not having any luck whatsoever. This for me is also a very recent problem….

    1. HA wrote on :

      Also in addition, the silverlight plugin does not appear in my add-ons manager.

      1. Jorge Villalobos wrote on :

        In that case the plugin is not installed or Firefox can’t find it. Maybe removing it and reinstalling would fix the problem, but I’m not sure what could be wrong.

  11. acaperto wrote on :

    I have found that Firefox (23.0) is installing the Netflix Silverlight package (created 5/14/2013) and then blocking it. The information at the top of the page is not correct. Firefox is blocking *all* versions of Silverlight. Fortunately, going to tools/add-ons/plugins shows you the disabled plugin and you can enable it over on the right-hand side. I set it to always activate – we’ll see how long that setting is honored! There’s an hour of my life I’ll never get back!

    1. Jorge Villalobos wrote on :

      Which version of Silverlight do you have installed?