I have relegated my 520 as a backup phone, but I carry it around with my every day as a mini (or micro) tablet. I use another phone as my primary, and obviously, I keep my SIM card in that phone. Now that I have the 520 without a micro SIM, Here Drive will not work or even open. Has anyone had luck using an older "expired" micro SIM placed in the slot to get Here Drive GPS to work? I know that I can take the sim out of my main phone and place it in the 520, but it's inconvenient. I cut an old standard size SIM from an old flip phone and put it in the 520, but no luck. I do get a message upon booting the phone that it's in GSM mode. If anyone has any suggestions, I would appreciate it. I haven't tried downloading maps with the active micro SIM in the 520 and seeing if Here Drive will work after removing the SIM.