I have an external HD called "Macintosh HD". It use to be my main drive and has since became my backup. I deleted some music from Macintosh HD (about 20GB worth) which went into the trash. Then with my external HD unmounted, I tried to delete the items in trash. Obviously it didn't work since my external HD was unmounted. Instead of putting 2+2 together, I immediately used an application called "trash it" to delete whatever was in my trash. The "trash it" application immediately emptied the trash but I notice that the free space isn't showing up on my external HD.
I tried to delete the .trashes and .trash file on the HD to no avail. When I used "Omnidisksweeper" I see the discrepancy in free space vs total space. (screenshot attached). I am not sure what to do!!! Where are those files in Limbo?
Here is a screenshot. http://imgur.com/aHrLB