|Does your computer have a memory card reader ?|
If yes, if you don't use Safely Remove Hardware to STOP accessing the drive letters, each drive letter in My Computer will have the label Removable Disk if it has no card in it or if it does but the card has no volume label, or if a card has a volume label the label for the drive letter will be the card's volume label.
If you DO have a memory card reader, if you DO NOT want to use it, you can get rid of the drive letters by
- open up the case and unplug the USB connection that comes from the card reader on the USB header
- when you have NOT used Safely Remove Hardware to STOP accessing the drive letters, RIGHT click on My Computer - Properties - Hardware - Device Manager
Open up Universal Serial Bus controllers, RIGHT click on USB Mass Storage Device - Properties - at the bottom of that small window - Device usage, select Do not use this device (disable), click on OK at the bottom of that small window.