KB: File type not recognised when opening a PCB document

Solution Details

An unexpected event, such as a crash or shutdown while saving a PCB document, can cause an empty or corrupted file. When opening this file, the warning File type not recognized may occur, and the PCB may be empty.

What can be done to avoid data loss in such a case?

Let’s first look at what happens while saving a project document. As a first step, the previous version of the project document is archived in the folder History in the projects directory. The next step is to save the data to a temporary backup file <file_name.$$$> if the data is to be saved to an existing file. As the last step, the previous file version will be replaced by this backup file as the current version, e.g. <file_name.$$$> to <file_name.PcbDoc>.

So, when an unexpected event happens during saving, there is a chance that even if the project document itself is corrupted, the saved data is in the *.$$$ file in the project directory.

Navigate to the project directory and check whether there is a file with the extension *.$$$. If so, please rename this file to have the correct extension, e.g., <file_name.$$$> to <file_name.PcbDoc>. Check if opening the file is working and if this solves the problem. 

If no *.$$$ file exists, you can at least restore the previously saved version of the file from the History folder.

The Storage Manager Panel provides access to the Local History feature, allowing you to revert to a previous document version.

More sophisticated version control capabilities are available Using External Version Control.

The most advanced form of working with projects under version control is to use the capabilities of a connected Altium 365 Workspace.

For a project managed through a connected Altium 365 Workspace, the detailed Project History can be accessed by right-clicking on the project file in the Projects panel and choosing History & Version Control » Show Project History.

As a final note, Auto Save functionality is available to automatically save a backup of the documents you are working on at a defined time interval in the background.