Message “VI Already Exists and You Do Not Have Permission to Replace It”

Updated Feb 13, 2024

Reported In


  • LabVIEW

Issue Details

I am trying to save changes I have made to a VI/project/control, but I keep getting the error:

Cannot save VI (project or control) " VI name .vi" ("Project name.lvprj" or "Control name.ctl"). The VI already exists and you do not have permission to replace it.

What am I doing wrong?


This error will occur when the VI has been set to read-only in Windows.

Note: You could require administrator level access to edit this setting and perform this and other user permission changes mentioned in this article

You can change this setting by:

1) Right-clicking on the file or directory in Windows and selecting Properties.
2) If the Read-only checkbox is checked, LabVIEW will not have the ability to change the contents of the file. Deselect the Read-only checkbox to allow LabVIEW to save the VI.

If this message shows up when saving a LabVIEW project, you should change the Read-Only Attribute for each component of the project. 
If this happens for all the files that are inside a folder, you can change the Read-Only Attribute in the folder containing all the files. 

On recent LabVIEW versions, the VIs associated with LabVIEW toolkits and NI drivers are now being placed under the directory C:\Program Files\NI\LVAddons, this could cause some files to have this setting there by default and if this error is giving you issues for VIs in this location. You can additionally try:
  1. Opening LabVIEW as administrator and see if that allows you to save the VI.
  2. Edit Windows permissions for the file or directory to allow Write/Modify permissions or Full control for your user profile.
    1. Right-click >> Properties for the file or directory that you are trying to modify.
    2. Navigate to the Security tab and check if the Users profile (or the one you are using) has Full control or Modify/Write permissions.
    3. If the permissions are missing, click on Edit (administrator permissions required).
    4. Select again the Group or username you are using, modify the permissions to enable Full control with the checkbox.
    5. Confirm the changes with the desired combination of Apply and/or OK.
Windows permissions.png