WINDOWS INTERNALS: After developing the Sysinternals suite and many other essential tools for Windows, Mark Russinovich now serves as Azure CTO at Microsoft. However, one of the longstanding software issues he encountered throughout his programming career continues to plague Windows to this day.
In a recent video published on the "Microsoft Developer" YouTube channel, Russinovich offered a concise explanation of what the "file is in use" error message means when Windows refuses to comply with a request. The creator of Sysmon, Process Explorer, and other popular Windows utilities discussed file handles and why Windows may have legitimate reasons to block a user's attempt to delete a file that is still in use.
Russinovich has been dealing with the notorious "file is in use" error since the 90s. He created Handle and Process Explorer to quickly diagnose and resolve this type of software issue. A handle is an abstract reference to a resource used by an application, such as a memory block, a file, or an object managed by another subsystem, including a database or the operating system itself.
When a handle is preventing a user from deleting a file, Russinovich explains, there are usually three possible explanations. First, the file may be locked by an anti-malware or antivirus program while it is being scanned. Second, the file may be in use over the local network, with another machine performing a storage-related operation.
