Sometime just after I launched a new emulator, for very first time I was trying to upload my apk, however I got "emulator: ERROR: the user data image is used by another emulator. aborting".
I launched a new emulator, and left it alone, several minutes later, DDMS showed "device offline".
I had to restart a new one, you know, minutes wasted.
It's really bothering that I keep getting this error and slowed down debugging.
How do I fix it?