Due to a problem caused by software from a leading backup service (I'll leave them nameless), I had several copies of a file in the Trash that OS X Mavericks thought were zero-byte applications, that were locked, and were flagged as "in use". There seemed to be no trick or technique to get those files to go away. I even reinstalled Mavericks. No joy. Then I read a mention of TrashIt! in some blog. I downloaded and tried TrashIt! and my problem was immediately solved. This app is terrific. Don't hesitate to send a donation to the author -- they deserve it.

Wow! ***Thank*** you! I've had trash stuck for a year - tried scripts all over the place. This solved it in *seconds*. Very slick. I wish I could have donated more than I did.

Simply put, it works! Tried a bunch of other programs before this one saved my sanity. Thank you. Made a dontation while I was at it.

In getting rid of old Time Machine files, I find that if you turn off time machine application but keep on your time machine storage device, you can get rid of them after 20 minutes or so with no error message. I am giving Trashit the credit for this but it took a few days to work out the formula of Trashit/time machine/storage working together - It's wonderful to get out of that 8003 loop of frustration

Well, Trash It! did not work quite as described, but finally it did do what I needed - so THANKS and a donation is coming.
I had the dreaded 8003 error message when trying to empty Trash on my iMac. Based on positive reviews, I downloaded Trash It! I double-clicked the TI icon and got encouraging messages indicating that my Trash can would shortly show empty (sorry, forget the actual wording), but the Trash stayed resolutely full with about 5000 items – both when I selected Fast and again when I later selected Really Stuck.
I then started taking individual items from the Trash, putting them on Desktop, then dragging them onto the TI icon. Slow, but this worked, and I eventually got brave enough to remove hundreds of items at a time until I finally reached some magical point where I had removed some unknown offending item from the Trash can, after which the Finder's own Empty Trash did its job of emptying trash.
Perhaps not elegant, but success in the end thanks to Trash It!.

I am trying to use Trash It to empty my trash from manually attempting to clean up/delete Time Machine backups on my external hard drive (which was getting low on space). I downloaded Trash It, moved the "contents to the desktop" from the zip file, launched the program, ran it with only a normal delete and now it has been running all night long saying it is "Unlocking Volume Trash...". The external hard drive is 750 Gig in size....based on the posts, it looks like this should have run and been pretty quick. I have tried to kill Trash It and restart, but that did not appear to work, though it disappeared off my "dock". Any ideas on what could be happening? OS is 10.6.7 and the machine is an iMac. Thank you in advance for your help.

Trashit 3.6.1 did not delete {"Just Delete"} a folder in trash named Coby MP-C440 which has over 200 identically named folders nested within. It seemed to run, presenting gui for password and messages on the progess window. After 15minutes it declared all done, but trash still contained the nested Coby folders. OSX Emtpty trash reports 234 items, runs a couple of minutes, but does not empty trash. Cannot rename them when they are not in trash. Info says size zero.