.LCK File Extension
What is an LCK file?
An LCK file is an access control file used to "lock" a database or other file from being opened or changed by more than one user at a time. It prevents users from accidentally overwriting changes and possible data corruption. LCK files are typically open when the file is not in use and locked when a user is working on the file.
LCK files may be used by a variety of programs and databases. Some programs that use LCK files include Microsoft FrontPage, Corel Paradox, Adobe Dreamweaver, Autodesk Inventor, Pegasus Mail, and ACT! contact management software.
NOTE: Since lock files are managed by their corresponding applications, they should not be opened manually.