Locking The Block Diagram in LabVIEW

Updated Dec 15, 2022

Reported In


  • LabVIEW Base
  • LabVIEW Full
  • LabVIEW Professional

Issue Details

  • I want to lock my VI in LabVIEW so that only certain people can view or edit the block diagram and front panel.
  • I am having trouble colleagues editing my VI, and not being able to determine what changes were made or how to revert them. I would like create a version of this VI that only I can edit.


In LabVIEW 5.0 and later, it is possible to password protect a VI, which allows you to distribute the VI without giving access to your source code. 

Be aware that if a VI is password-protected and you do not have a password for it, there is no way of unlocking the VI. For security reasons, National Instruments cannot unlock password-protected code. You should always keep a backup of your files stored without passwords in a secure location.

To password-protect a VI, navigate to File»VI Properties. Use the drop down menu to select the Protection category, select Password-protected. You will then be prompted to enter your password. The password will take effect the next time you launch LabVIEW.

Additional Information

If you need total assurance that your source code is not accessible, consider using the Remove block diagrams feature. Be sure to back up your VIs before using this technique, as the block diagrams cannot be recreated. Please note that removing the block diagram prevents the VI from being opened in earlier or later versions of LabVIEW, does not allow for future edits of the VI, and does not allow the VI to be opened in different operating systems.