Message: The file appears to be locked.

Reference Number: KB-00964
Last Modified: March 24, 2022

The information in this article applies to:

Chief Architect Premier or Chief Architect InteriorsHome Designer Professional or Home Designer Architectural or Home Designer Suite


When I try to open or save a particular file, I receive one of the following error messages:

"The file appears to be locked. This could be the result of another user or program using the file. This may also result from having insufficient security privileges to access this file."

"Unable to write to file. The file may be locked by an active plan or layout."

"Unable to write to existing file. Verify the file is not open or locked by another application."

What do I do?


There are a couple of broad reasons why one of these errors may occur:

  • The file might already be open in an application, possibly by another Chief Architect user.
  • Your current user account for this computer may not have sufficient rights (privileges) to save or open the file.

The best way to resolve this issue will depend on the cause. 

If the file is already in use

There are several scenarios in which a Chief Architect plan or layout file that you wish to open might already be in use elsewhere. It could, for example, be:

  • Open in another version of Chief Architect or Home Designer running on your computer;
  • Open in a session of the current version of Chief Architect or Home Designer that has not completely shut down and is running in the background on your computer;
  • Open in a session of Chief Architect or Home Designer running on another computer on your network, which is not recommend nor supported.

The first of these scenarios is easy to resolve - if another version of Chief Architect is running, simply save your work and close the file. The second scenario requires a little bit of investigation. Save your work, close your Chief Architect or Home Designer software, then navigate to the appropriate section below that corresponds to your operating system. The third scenario means that the file may be stored in a shared location on this computer or on another system that is connected to your local area network, and the file is being used or edited by another process on that system.If the file is locked because another user on the same network has it open on their system, then you can have them close the file so that you can open it. If it is locked and does not appear to be in use on any other systems, restart all the computers that are connected to the network and try opening it again.

Working on files from a shared location or external storage device can cause problems, such as slow performance and file corruption/data loss. As a best practice, we recommend copying projects to a local file location on your computer while working on them. After you're done working on the file, close the program, then copy the file back up to the shared location. Please see KB-03155: Sharing Projects in a Work Environment that is Utilizing Cloud/Network Services to learn more.


  1. Press Ctrl + Shift + Esc on your keyboard to open the Task Manager.

    Alternatively, you can access the Task Manager by performing a search on your computer for "Task Manager" or by pressing Ctrl + Alt + Delete on your keyboard and clicking on the Task Manager option.

  2. Click More details, select the Processes tab, then browse the list for any instances of Chief Architect or Home Designer.

  3. If you find an instance of your software still running, select it and click End task to terminate the process.

    Select the Chief Architect or Home Designer program and choose End task.


  1. From your Desktop, navigate to Go> Utilities from the menu bar.

  2. Open the Activity Monitor app.

  3. If you find any instances of your Chief Architect or Home Designer software still running, select it and click the Stop Stop button in Activity Monitor button.

    Activity Monitor application on macOS

If you do not have adequate user rights

If you are sure that the plan or layout file is not already in use elsewhere, then it is likely that your user account for this system does not have sufficient rights to access the file where it is currently saved.

One way to avoid this issue is to have the user that created the file(s) copy them to a location that you have access to - for example, the Public user's Documents directory.

To learn more about file and folder permissions for individual users on your computer visit the Microsoft or Apple website.