LCK file icon

LCK File Extension

Program Lock Format

What is LCK file?

LCK is a type of resource lock file. LCK extension is added to the filename of the file being locked, for example, locking a document.DOC file will result in creation of a document.doc.LCK file responsible for locking the original file. LCK files are typically empty, but some programs may store additional data related to the lock inside such files. LCK files should not be edited manually.

How resource locking works

Each locked file is prevented from being written to. Application that blocks given file usually keeps LCK active to prevent the original file from being deleted. Locking mechanism is commonly used by database engines, spreadsheet applications, or even DOC files. Locking can also be used when multiple users access the same file. In such case, the LCK file tracks which user has access to the file or its part in given session. Different applications implement locking mechanism differently.

Programs which support LCK file extension

The following list contains programs grouped by 3 operating systems that support LCK files. Files with LCK suffix can be copied to any mobile device or system platform, but it may not be possible to open them properly on target system.

Updated: 04/28/2022

How to open file with LCK extension?

Problems with accessing LCK may be due to various reasons. Fortunately, most common problems with LCK files can be solved without in-depth IT knowledge, and most importantly, in a matter of minutes. The following is a list of guidelines that will help you identify and solve file-related problems.

Step 1. Get the Referenced by various applications

Install software to open LCK file Problems with opening and working with LCK files are most probably having to do with no proper software compatible with LCK files being present on your machine. This issue can be addressed by downloading and installing Referenced by various applications or different compatible program, such as Microsoft FrontPage, Adobe PageMaker, Pegasus Mail. The full list of programs grouped by operating systems can be found above. If you want to download Referenced by various applications installer in the most secured manner, we suggest you visit website and download from their official repositories.

Step 2. Update Referenced by various applications to the latest version

Update software that support file extension LCKYou still cannot access LCK files although Referenced by various applications is installed on your system? Make sure that the software is up to date. Software developers may implement support for more modern file formats in updated versions of their products. The reason that Referenced by various applications cannot handle files with LCK may be that the software is outdated. The most recent version of Referenced by various applications is backward compatible and can handle file formats supported by older versions of the software.

Step 3. Assign Referenced by various applications to LCK files

After installing Referenced by various applications (the most recent version) make sure that it is set as the default application to open LCK files. The next step should pose no problems. The procedure is straightforward and largely system-independent

Associate software with LCK file on Windows

Change the default application in Windows

  • Choose the Open with entry from the file menu accessed by right-mouse clicking on the LCK file
  • Select Choose another app → More apps
  • To finalize the process, select Look for another app on this PC entry and using the file explorer select the Referenced by various applications installation folder. Confirm by checking Always use this app to open LCK files box and clicking OK button.
Associate software with LCK file on Mac

Change the default application in Mac OS

  • Right-click the LCK file and select Information
  • Open the Open with section by clicking its name
  • Select Referenced by various applications and click Change for all...
  • Finally, a This change will be applied to all files with LCK extension message should pop-up. Click Continue button in order to confirm your choice.

Step 4. Verify that the LCK is not faulty

You closely followed the steps listed in points 1-3, but the problem is still present? You should check whether the file is a proper LCK file. Being unable to access the file can be related to various issues.

Check LCK file for viruses
1. Check the LCK file for viruses or malware

Should it happed that the LCK is infected with a virus, this may be that cause that prevents you from accessing it. It is advised to scan the system for viruses and malware as soon as possible or use an online antivirus scanner. If the LCK file is indeed infected follow the instructions below.

2. Check whether the file is corrupted or damaged

Did you receive the LCK file in question from a different person? Ask him/her to send it one more time. It is possible that the file has not been properly copied to a data storage and is incomplete and therefore cannot be opened. When downloading the file with LCK extension from the internet an error may occurred resulting in incomplete file. Try downloading the file again.

3. Check if the user that you are logged as has administrative privileges.

There is a possibility that the file in question can only be accessed by users with sufficient system privileges. Log out of your current account and log in to an account with sufficient access privileges. Then open the Program Lock Format file.

4. Check whether your system can handle Referenced by various applications

If the systems has insufficient resources to open LCK files, try closing all currently running applications and try again.

5. Verify that your operating system and drivers are up to date

Up-to-date system and drivers not only makes your computer more secure, but also may solve problems with Program Lock Format file. It may be the case that the LCK files work properly with updated software that addresses some system bugs.

Do you want to help?

If you have additional information about the LCK file, we will be grateful if you share it with our users. To do this, use the form here and send us your information on LCK file.

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