The Cessna key registers the Cessna Detail Pack Add-on for FSFS2010 or FSFS2009.

In order to fly outside the demo area you need to register FSFS2010 itself.

Note that the Cessna Detail Pack Add-on and FSFS2010 are 2 separate products with 2 registration processes and keys.

From what you have explained it sounds like you have not purchased FSFS2010 itself?

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FSFlyingSchool - Fly like the Pros with Flight Simulator

Happy landings.

Squadron Leader
FSFlyingSchool - Fly like the Pros with Flight Simulator