An attempt to open a file that is being used by another program. In a normal single-user environment, if an application has already called in a file (document, spreadsheet, etc.), and another program tries to read it, a sharing violation occurs. The solution is to close the file, which releases the "lock" placed on it by the application that opened it. Network Files Can Be Shared In a network environment, files can be made sharable for multiple users. If the data are only read and not changed, multiple applications (users) can read the file at the same time. If the file can be updated by multiple users, the operating system or DBMS must manage access to the data via file and record locking or other tracking mechanisms. See file and record locking.