Loss of Drive Letter – If the drive letter of an SD Card is lost, it will not be detected. Locked SD Card – An SD card that is write protected cannot be read by the PC and it will not show up. Poor Connection – The SD card might not be properly connected to the PC because of a damaged card reader, adapter or USB port.ĭriver Problems – The card driver may be outdated or corrupted if the SD card does not show up in system but can be seen in Device Manager.
