Can't delete folder in Windows 8

You can use command line utility Handle by Microsoft Sysinternals. It can tell you which process holds file or directory open, like this:

handle c:\mydir

This will show which process holds directory open, if any.

You can also use Process Explorer, but you will have to search for your file/directory using Process Explorer UI.

While this works, I still find it too complicated, because I use Far Manager all the time, and FAR is helpful enough to show list and offer to kill processes that hold my files open if I am trying to delete them using Far Manager interface.

This is often because Windows search index is being updated. Try the following:

In File Explorer, right-click on the offending folder. Choose 'Properties'.
Make sure you are viewing undr the 'General' tab, and click Advanced.
Untick box 'Allow files in this folder to have...' etc. (if it's not ticked when you open Advanced Attributes then this suggestion is the wrong one for you...) and click OK.

Try to delete the folder again. (if unsuccessful, then this suggestion is the wrong one...).

Click 'Advanced' again, and re-tick the 'Allow files in this folder...'etc. Click OK and close the Properties window.

Lockhunter is the program I use to handle this issue. Please note, I am on Windows 7, and it doesn't claim Windows 8 support, although it can't hurt to try it out. It will use a GUI interface to tell you which process is locking a file, and offer to kill it and delete the file.

Also, it adds a context menu option, which makes access to this functionality quite easy.