This issue is most commonly encountered when the object you're trying to remove from your project is present in an auto-populating folder. Auto-populating folders link to an existing file location in your file system, and populate their contents based on the contents of the file location they're linked to. Files in an auto-populating folder are only present because they appear in the linked file location, and as such cannot have their file location edited from a LabVIEW project.
In order to remove files in an auto-populating folder, you need to either:
- Disable auto-populating on the auto-populating folder, or
- Remove the file you want to remove from the linked file location.
You can disable auto-populating using the context menu for the auto-populating folder in your LabVIEW project.