I just started having this problem. I've tried connecting/reconnecting my phone, rebooting, and removing/inserting my SD card.
At work I'll connect my phone to my PC via USB. I never change it from PC Mode. Today when connecting my phone, my SD card unmounted itself, like it would when switching to USB Mass Storage. Even when switching to Charge Only the SD card will unmount. Disconnecting the USB cord from my phone is the only way to remount the SD card. Any suggestions?
Edit: I figured out what the problem was. I recently installed WinAmp, which has an option to Auto-mount the SD card to a PC when connecting via USB. Turned the option off and now it's running correctly
At work I'll connect my phone to my PC via USB. I never change it from PC Mode. Today when connecting my phone, my SD card unmounted itself, like it would when switching to USB Mass Storage. Even when switching to Charge Only the SD card will unmount. Disconnecting the USB cord from my phone is the only way to remount the SD card. Any suggestions?
Edit: I figured out what the problem was. I recently installed WinAmp, which has an option to Auto-mount the SD card to a PC when connecting via USB. Turned the option off and now it's running correctly