I have been using Gravity Forms for several months and all works well. However, for the past couple of upgrades the "Register your copy of Gravity Forms to receive access to automatic upgrades and support. Need a license key? Purchase one now." line is permanently in my PlugIns list page. The plugin IS registered and the Green Tick appears on the Gravity Forms page.
I notice that a couple of other forum posts (now closed) have existed on this topic recently, but no solution has been provided.
It would seem there is some kind of bug...?