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In the registry Mozilla plugins cannot be deleted but one is blocking installation of MS Silverlight update. Any suggestions?

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  • Last reply by cor-el

52545864
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Microsoft has been trying to update Siverlight for the past few weeks - each time failing. It says that HKEY_LOCAL_MACHINE\SOFTWARE\MozillaPlugins\@Microsoft.com/NpCtrl,version=1.0 is the problem. I have tried to delete it & the whole Mozilla key but I get 'Error while deleting key. Access is denied', in every case. There are 14 items under MozillaPlugins.

I reinstalled Firefox to see if it would 'kickstart' the string, without success.

MozillaPlugins:Name (Default); Type:REG_SZ; Data:(value not set). Windows 7 Home Premium.

I am the main administrator - confirmed in cmd - but anything I enter into Permissions is refused.

Microsoft has been trying to update Siverlight for the past few weeks - each time failing. It says that HKEY_LOCAL_MACHINE\SOFTWARE\MozillaPlugins\@Microsoft.com/NpCtrl,version=1.0 is the problem. I have tried to delete it & the whole Mozilla key but I get 'Error while deleting key. Access is denied', in every case. There are 14 items under MozillaPlugins. I reinstalled Firefox to see if it would 'kickstart' the string, without success. MozillaPlugins:Name (Default); Type:REG_SZ; Data:(value not set). Windows 7 Home Premium. I am the main administrator - confirmed in cmd - but anything I enter into Permissions is refused.

Chosen solution

You will have to change the permissions of that key via the right-click context menu.

See also:

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cor-el
cor-el
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Chosen Solution

You will have to change the permissions of that key via the right-click context menu.

See also:

52545864
52545864 Question owner
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Thank you. I am obviously not doing the right thing as all of my suggested entries, to change the Permissions, are rejected. For instance, what is the name of the object? I have tried various permutations without success.

Post Script: have just run Microsoft's Fixit (kb2608523) & it did. I don't need to worry about deleting the Registry Key, now

Modified by 52545864

cor-el
cor-el
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Did you give yourself write permissions for this registry key?

You may nee to go up a level and apply the permission to sub keys:

  • HKEY_LOCAL_MACHINE\SOFTWARE\MozillaPlugins