Hi all,
I too acquired the mysterious padlocks after updating my 550t to 2.60.
After a lot of messing about, in desperation i clicked on reset--reset trip data etc, deleted all waypoints and cleared current track memory.
It seems to have worked for me--the padlocks have now disappeared (for now!!).
I don't know if i will experience any other problems such as freeze ups etc--not going out in this weather!
Hope it works on yours.
John.