unregister dll

portable applications like liberkey, i make the 7-zip to add right click menu / integration to shell context menu
I know I should unregister this function before I delete the liberkey,
but I didn't make it, and now the 7-zip.dll remains locked, because it is loaded into memory

so I need to manually unregister the dll and delete it

use regdllview from nirsoft
or
regsrv32 /u path-to-dll\7-zip.dll