I don't have your machine so I can only give you a few suggestions. Firstly, are you sure that the designs are in the correct format? Secondly, is there a specific folder on the dongle where they must be saved?
If you don't get any joy on this forum, go to the Martha Pullen embroidery forum - very active and knowledgeable.

In order to save the designs to your USB stick so that they can be read by your machine, you must add them using the disk manager.

HTH,
Bobi

I have the Designer SE, but I think this still holds true: I don't think you are supposed to download onto your "dongle." The "dongle" stays in your USB port on your computer when you're managing your design. Use your red USB stick to download onto, then to transfer the design to your sewing machine.

When I purchased the Customizing & Dig software package, it was supposed to come with a dongle. Well, it didn't and I never used it because I was so busy then and using the machine was just for sewing. Anyone know where a dongle can be purchased? Viking never replies to any of the 50+ posts I've sent them asking. I'd never buy another, that's for sure. Totally disappointed.

Go to your Husqvarna-Viking dealer and get one. Or ask them about it and they'll order it for you. They are usually in all JoAnn Fabric stores.