.IDLK File Extension
File TypeAdobe InDesign Lock File
File format categories include Binary, Text, XML, and Zip. The format of this file type has not been determined.
What is an IDLK file?
Source control file created when an InDesign (.INDD) file is opened; allows the file to be "checked out" and prevents the InDesign document from being edited by more than one person at a time.
InDesign lock files typically use the following filename convention: "~[INDD filename]~[random string].idlk." They are saved in the same folder as the InDesign files they represent. Leftover IDLK files can be deleted after the InDesign application has been quit.