Safely "unmounting" USB for Galaxy? I wanted to delete all of the music (not pictures or apps) off my phone, and I read that you should just plug it into the computer and delete them from there. I plugged it in, and though my phone is charging, it hasn't recognized my device. I want to unplug it, but there is message warning me to unmount the USB before I unplug. Will it delete all of my memory if I do? Can I just back up and reset my phone while in this mode, or will my things be deleted?
No, nothing will be deleted if you chose to "unmount" first. As your device was not detected, it should not even be mounted, so there's nothing that could "break".



A short explanation on that "mysterious unmount", though:

If your device is "mounted" (i.e. you can access its files from your computer), for faster reaction and other performance reasons all data transfered is "buffered" (instead of being written to the storage immediately). So "unmounting" tells the system to "flush" those buffers, and thus "commit" (write) all buffered data to the storage.

If you would simply "plug the line" without unmounting first, not-yet-written data were lost. Imagine what that would mean if some larger file was only written partly (it gets corrupted), or if you moved files to the phone which where not yet written at all (they are "lost in space").

So it's always a good safety measure to "unmount" first before plugging out the cable.