When a Thumbs.db file cannot be removed because an error shows that a process has the Thumbs.db file open, then killing the process holding it open will free it up and the Thumbs.db file can be removed.
NOTE: It is likely that after killing the process holding the Thumbs.db file open that related processes will also be killed, such as Windows Explorer, so before killing the process, open a Powershell window and use the "cd" command to change the folder to the folder containing the Thumbs.db file:
e.g, if the Thumbs.db file is in c:\users\music the Powershell command would be: cd c:\users\music
To run Powershell press the Windows Key and r at the same time, then type powershell in text box)
Find the process that needs to be killed
• Run taskmgr (Windows Key and r at the same time, then type taskmgr in text box)
• Go to Performance Tab
• Open Resource Monitor (Bottom of Screen).
• In the Resource Monitor switch to CPU tab
• Select Associated Handles (Below list of processes)
• In the text box type Thumbs.db
• Select the process listed and Right Click to end (kill) the process
The Powershell window should still be available, to remove the Thumbs.db file the Powershell command would be: rm -f Thumbs.db
• If related processes have also been killed (e.g, some windows or the taskbar are no longer running) reboot Windows