Mapsource routes i can design a route on pc and load to zumo,but even though i can load to sd card with a view to loading it later to zumo the unit does not recognise those routes. i thought having them on sd card until you needed them would save the zumo memory. colin

There several reasons you may receive the message Can't Unlock Maps on your nuvi or zumo device.

• Can you press OK and get to the Where To/View map screen?
• Did you load maps to the unit using the MapSource or MapInstall program?
• Did you load maps to an SD data card?

If one of the points above applies to you, please follow the steps below to clear the Can't Unlock Maps message:

1. Remove SD card from unit, if applicable.
2. Plug the unit into your computer with a compatible USB cable.
3. Open MyComputer/Computer icon. (Mac users skip this step.)
4. Right-Click on the Garmin drive and select Open. (Mac users can locate the Garmin drive mounted on the Desktop.)
5. Open the Garmin folder.1
6. Locate a file named gmapsupp.img
7. Right-Click and delete file named gmapsupp.img
8. Safely disconnect your unit from your computer to see if the Can't Unlock Maps message is gone.

1. Nuvi 1100/1200/1300/1400/1600/3700 and Zumo 665 users will open the Map folder instead.

*If the gmapsupp.img file does not appear in the Garmin folder, please create an unlock file for device.

Check this link i think it will be helpfull for you:

http://www.pocketgpsworld.com/garmin-maps.php

From browsing the manual (page 20) for your Garmin nüvi 350, it looks like you will be able to do this by creating the route in MapSource, saving it as a GPX file, and then loading it to your nuvi on an SD flash memory card.

The Nuvi 350 doesn't support custom routes. You can create waypoints (or custom POIs) for each location and manually pick waypoints as you travel, but there is no way link all the points together into a route. While you can upload a GPX file to it, it won't contain the route, just waypoints. When you pick a waypoint and tell the 350 to take you there, it's going to calculate the route based on the settings (ie, vehicle type, shortest distance, etc). It won't follow a predetermined route.

1. Make a backup of your Zumo by copying all the file to your computer.
2. Using your PC and MapSource select all the maps then send them to a SD memory card need 2Gig or bigger card.
   
3. Try to rename this file to gmapprom.img and replace the same named file in your zumo. (I haven't tried this personally, so if it fails, just replace this with your backup and all will be as it was.)
   
4. If this fails, you can use the SD memory card in your zumo and it will use this map instead, but it will take longer to boot your zumo.
   

Import to pc or to garmin device? There is some info in the manual, however you will need an SD card to work with triplogs.

I have found that waypoints, routes and directions work only when I load it on the unit itself as opposed to the SD card. The SD card works more like an expansion slot for pictures or maps.

When you open up Mapsource you'll see the map on the right and the pane on the left, above the pane there are 4 tabs (Maps, Waypoints, Routes and Tracks). As you select a map or create a waypoint, route or track. It will put a number in parenthesis which will increase in numbers as you add an item corresponding to each category, for example if you create a waypoint. So once you have done that, click on the TRANSFER tab in the Menu selection bar and choose SEND TO DEVICE. A window will pop up that will say...Device: with a drop down menu if your Garmin unit has an SD card in it, if not it will just show the Garmin unit. Then right below that there will be a section that says WHAT TO SEND with 4 check boxes that will say Maps, Waypoints, Routes and Tracks. Make sure that you have selected the Garmin unit, not the SD, and the waypoints, routes or tracks you want to send. I hope this solves your problem or at least points you in the right direction...

Do you see a map, with street detail? Any SD card installed?
Tap the wrench symbol, tap mapping, tap about, any maps checked? if not, check the apropriate map and go back to the map screen

How do you load maps? and are these Garmin maps. I try to keep the Zumo original and use an SD card for extra maps. Did you try this yet? And if you are using SD cards, try a different brand/quality. I had some lockups with crappy budget cards. Kingston, Sandisk and some other A brands work fine!

If you don't have "Detailed Maps" for the area you are travelling in, it will not have adequate map detail to create routes that are not on major highways.

To remedy this, you will need to use another of GARMIN's products... I believe it's called Mapsource City Navigator, and will have to be purchased for the area you are concerned with. This PC software will then allow you to load additional Map Data onto an SD card, which will slip into the slot on the left side of the unit.

You can find out about it at their website www.garmin.com then look in Maps

Verify that you have the correct basemap for the country that you are in. There are two maps inside a new Garmin. The basemap which shows all the major highways and mapsource which shows all the street. If you don't have the correct basemap try changing 'Navigation' Advoidance to avoid highways and Toll Roads.