Hi Butters, thanks for your help - (post edited!).

The maps I want to use (City Navigator Europe 2019.20 and Topo Great Britain Pro) are unlocked with gimg - 0.04. They work fine in the 600 but not the 610. I looked again at the drive on the 610 (using Windows and Mac), there is no System folder nor GCD file. I think I'm looking in the right place as I can see the system file on my Zumo 590.

Any ideas?

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