I would like to join everyone else on here in thanking you!
Managed to get my nuvi 610 soaking wet with orange juice - (dont tell me about children!) the screen started to flicker then it died - and I noticed fluid draining out of the mini-USB port!
Diagnosed the fluid as juice (tentative taste!).
Placed unit on radiator to dry for a two days - then dreaded Software Missing message.
Attempted fresh software update - but said file corrupted - and still wouldnt work.
Tried holding the on button down - but gave up too soon!
Read this post, kept holding it down - and voila - a fixed unit!
Had the "system software missing" problem after accidentally drowning my Garmin Nuvi 600/650. Tried your recommendations after allowing it to fully dry and it fixed the problem. GPS is working great once again.
Nick, I don't know if you'll ever get to read this because you had posted this solution almost 7 seven years ago! I just wanted to say "THANKS" for the solution you posted. It worked for me and saved my GPS! I'd been playing with my Nuvi 660 trying to update the maps on the Garmin website. I have Lifetime Map Updates, but kept getting the mesaage saying my device hadn't have enough memory! It's been a common problem from what I've read. So anyway I started deleting files to hopefully free-up enough memory and, of course, messed-up my Nuvi 660 having deleted too many files. I ended-up formatting the entire device memory using DISKPART from the command prompt in Win 7, but the Garmin Express updater then could no longer recognize my Nuvi, of course. After using your solution - holding down the power button, waiting what seemed like a minute until the Pre-Boot words disapeared then going thru the procedure to set the touch screen to work? - I then noticed my 660 had re-installed some files and these were the files I had needed for the Garmin Express updater to recognize my Nuvi! From there I was able to update the newest maps for North America, two American English TTS voices (Jack and Jill) and one orange sports car To install these files within the Garmin Express updater I had to click-on "device" then "advanced". When finally finished all the updates I had only 6.15MB of free-memory available on my 660 and was happy as a pig in poop! I didn't have to go out and buy nor install a media card to get full coverage mapping of North America! Thanks again Nick for your post as it saved me a couple of hundred dollars!