How to clean up old application folders from prior ROM? I installed CM10 on my GS2, and during the process I didn't format the file system as I wanted to retain my photos and music on the device.  I was aware of an app called "SD Maid" that is supposed to be able to be able to clean up all these old app folders, but it doesn't seem to work.  Does anyone know how I can clean up all these folders, or does a person have to just go in and manually delete all of them?

(For an app to do this, the OS would have to have some sort of a referencing system of known installed files &amp; folders, don't know if it has such a thing though.)
If you're changing rom (I.e. from AOKP to CM10) you should always do a factory wipe, data on the sdcard will still be 

I'm amazed it booted if you didn't do a factory wipe before flashing a different rom