Head to whatever control panel that sets what the default web browser is and set it to IE. Test to see if the message vanishes.
Now open Firefox and see if it wants to update the application or addons. Let it finish that.
After this is all done, change the default browser back.
Sorry, no, I can't explain why we have to dance.
Bob
When I opened Outlook today, I received my regular emails, including the weather and news emails from our local news people.
When I clicked on the story I wanted to open in Firefox I got the
following message: This operation has been cancelled due to restrictions
in effect on this computer. Please contact your system administrator.
I'm the administrator and didn't put any restrictions in effect that I know of!
The only thing I've done in the past couple days is install and
uninstall chrome, and allow changes to registry by prompt from SpyBot.
I checked other emails that I get that have links to open in Firefox,
and they all come up with this same message and won't open anything.
I have restarted my computer to no effect.
Can anyone help?

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