Via eBay bought a nuvi 250W which was apparently used by a car rental agency prior to the sale. I got rid of the company logo on the splash screen by simply replacing the splash screen, but am unable to get rid of the reference to its previous use during start-up (see screenshot below):

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I tried Tools -> Settings -> System -> Restore, but that did not help.
I tried to flash older FW and then the current FW with WebUpdater, but that did not work either.
Probably the reference is embedded in a particular rgn, but that is where my knowledge ends.
Some guidance would be appreciated. I do have another nuvi 250W if that is of any help.