Transfer files via USB from PC Windows will recognize my Sony tablet, but the external SD card does not show, only the internal memory, I have the settings in the MPT mode. But can only see internal memory.
I have three suggestions:


If it is a MicroSD card, you could plug it into an external reader.
Try ADB (Advanced). If it shows up using the devices command, try pushing and pulling on the SD card.
Install file expert. When the app loads, the third tab has "Share my files" (Or something like that) Try these options via Bluetooth or WiFi. File Expert also has a seperate app, Web PC Suite, which can do the job you want.