Default Manager (Microsoft) has been blocked for your protection.

Why was it blocked?
This add-on has security issues and was blocked at Microsoft's request. For more information, please see this article.
Who is affected?
Users of version 2.2 of this add-on in all versions of Firefox.
What does this mean?

The problematic add-on or plugin will be automatically disabled and no longer usable.

When Mozilla becomes aware of add-ons, plugins, or other third-party software that seriously compromises Firefox security, stability, or performance and meets certain criteria, the software may be blocked from general use. For more information, please read this support article.