A new blank card will be formatted for FAT. You need to change it to FAT32 before it will work in the Spitfire.
Inset the card into your card reader (either usb or built in reader). Your computer will find the card and see it as a removable drive. Click your "start" menu, select "my computer". You should see that it has assigned a new drive letter for your removable card. Right click on that drive letter and select the format option. In the next options box that pops up you should be able to select between FAT and FAT32. Select FAT32 and click OK to format the card.
It may pop up a warning that all data on the card will be erased. Click OK and let it format the card.
Next and VERY IMPORTANT if you want to use the Foxpro software utility to load and arrange your sounds. The card has to be named SP1 before the Foxpro software will recognize it.
Go to My Computer, find the drive letter for your card and right click on it. Select Properties. Next, under the General tab you should see a blank line at the top of the box. Type SP1 and close the box.
You should now be able to transfer and arrange sounds with the Foxpro utility software.
You MUST have your sounds named 000 through 023 with a space between the numbers and the name of the sound. You MUST have 24 sounds on the card before they will work with the caller.
If you are unsure about your sound name, always select the "ammend sound name" option when you transfer a sound.
Always make a backup of your original sounds. I make a backup folder on my computer, another on an external hard drive and another on an extra SD card.
The Spitfire will recognize a 1gb or a 2gb card once it is formatted to FAT 32 but it will not work with a 4gb card.