[PeeHoo]

I get this error every time when I am trying to download app. Is there a way to fix this?

[cassiosouza]

same here just bought a lumia 620 and can't even download facebook.

[mixa8x]

This is the old problem and Microsoft did not do anything about that....The problem is probably in connection with xbox account... maybe you will find something helpful here:
Store - WP8 - Error: c101a006 - Microsoft Community