I did a search, googled, and finally am waving the white flag. I have fought this since yesterday. So here it goes, I have had my 610 for about 4-5 years, mostly spent in a case in my office. I used it on my Super Tenere for a while before I got a TomTom about 2 years ago. I decided to take it hiking last week to see if I could get some use out of it. Meh, kinda heavy, but worked fine. So yesterday I decided to just wipe it and put it up for sale. I followed Garmin's details on formatting the card. The detail that was left out is that was that you shouldn't format it WHEN ITS IN THE MONTANA. When I formatted it as a separate card on my Mac, it somehow deleted most of the OS off the damn 610's internal memory. So now the Mac nor a PC will recognize it. All of the profiles are gone except Recreational now. I have tried gpsrchive.com to reflash it, but it won't work. I contacted Garmin and they said I would just have to buy a new unit. Any ideas before I just toss this thing in the trash and start drinking? I have a decent amount of money tied up in Topo maps and City navigator maps. Sorry for rambling. I am a god awful writer.