Messages

Look two posts above... he was talking about 6.15.11 

The specs say you can upload maps, but it has no internal memory, just a data card. Is there a card in the slot? If so, does it already have a map installed? https://buy.garmin.com/shop/shop.do?cID=148&pID=401#specsTab

This is why I don't update any Garmin software unless necessary 

Here's an Oregon firmware problem I haven't seen before - loss of contrast in custom maps: https://forums.garmin.com/showthread.php?t=5653

New version of Mapsource just released: http://www8.garmin.com/support/download_details.jsp?id=209

There are several references to map unlocking. I wonder if this fixed the problems of 6.15.9 or if it has created even more?

Change History
Changes made from version 6.15.7 to 6.15.11:

    * Improved performance for custom draw elements.
    * Made sure waypoints of type 'Geotagged Photo' don't crash MapSource.
    * Allowed the import and export of unlock codes.
    * Made sure unlocking changes get propagated without needing to restart the application.
    * Phone numbers that were imported from gpx files were not written back out again. This is now fixed.
    * Added support for enhanced map security.
    * Fixed unlocking issue.
    * Implemented Asian 6-level address search.
    * Improved trimming performance for some Asian map products.

Sorry, I have never run into that. Exactly what maps are you trying to use? I don't understand why you would get the message about locked maps if they are OSM.

What happens if you just rename one of the files gmapsupp.img? I have done that before with an OSM file and it worked.

If they are pre-compiled .img files then you just need to change their names and put them in the right place. Create a folder named Garmin in the root of the SD card. Copy the .img file to the card, and change its name to GMAPSUPP.IMG.

Your unit will only recognize one map file and it must have that name. If you have multiple files, you will need to combine them somehow into a single GMAPSUPP.IMG. There are several ways to do that, but the simplest is probably to download the free Sendmap20 program here: http://cgpsmapper.com/buy.htm

Just drag all the files to the program's window. You can then either create a GMAPSUPP.IMG file on your computer or send it directly to the GPS.

My understanding is also that Garmin's map format only supports a maximum of 24 bit coordinates, and that limits the accuracy of any map to +/- 5 meters.

The order in which you do things is important:

FIRST - download and install Training Center
SECOND - download and install Mapsource
THIRD - download and install the maps from this site.

When you install training center, it places a crude basemap on your computer. When you install mapsource, it will see this map as a Garmin "product" and that will activate it. If you haven't already installed Training Center, Mapsource won't install because it doesn't find any Garmin maps on your computer.

The Garmin Topo US 100k maps are not terribly accurate either. I've never seen anything official, but most people assume the roads on these maps also came from TIGER data. The more expensive Garmin 24k topo's get their road data from Navteq.

The location of my own home and road are off significantly on Garmin's Topo 100k, but only by a couple hundred feet and not a half mile. But my point is, the 100k Garmin topo's are not going to win many awards for accuracy. 

Have you, perhaps, set marine mode in the suspect profiles? I think that might cause the water to turn white...

Different authors have created these maps themselves, so depending on their experience and what they hoped to accomplish with the map there can be big differences. If you ask for help with a specific map, the author or somebody else knowledgeable will probably respond. I have never used the Georgia map myself.

Well obviously I just wasn't paying attention with the old version    The trick is that you have to choose the GNIS option when you open the files I think. I know I tried opening them with version 9 and couldn't get it to work.

I found that it did a pretty good job with the PA data I downloaded the other day. There were some unknown point types, but that isn't an issue for me. I convert everything to either a generic dot or a custom MP_TYPE anyway - I hate the ugly standard symbols.

I don't see how anybody can generalize about "the free maps" since they have been contributed by many different people....

I just "discovered" that Globalmapper can now directly open downloaded CSV GNIS .txt files. Is that a new feature in version 11, or did I just never notice it before? Either way, it sure makes things easier! You just go to the open file menu in Globalmapper and choose GNIS as the file type.