This utility for Windows uses handle from Sysinternals to unlock a file. All open handles to the file by all processes are closed. This may cause the processes to malfunction, but sometimes freeing up the damn file is more important.
Usage:
java -jar unlock.jar [--list|-l] [path]
To add an Unlock entry to the context menu for all files and folders, place the following in a .reg file, modify the paths for your Java and unlock.jar files, and merge it into your registry.
Windows Registry Editor Version 5.00
[HKEY_CLASSES_ROOT\*\shell\Unlock]
@="&Unlock"
[HKEY_CLASSES_ROOT\*\shell\Unlock\Command]
@="\"C:\\path\\to\\java.exe\" -jar \"C:\\path\\to\\unlock.jar\" \"%1\""
handle is difficult to use directly because it lists the handles and expects you to assemble further commands to do the unlocking, which is tedious. Also handle uses substring matching, eg abc will match both abc and abcd. Checking for an exact match via shell scripts is cryptic and difficult to get right.
If substring matching is sufficient, handle can be used with Cygwin like this:
handle -nobanner -v "$1" | sed '1d' | cut -f2,4 -d, | tr ',' '\n' | xargs -r sh -c "handle -nobanner -p $1 -c $2 -y" sh