Background Information

A recent post in Microsoft’s Project Group user forum prompted me to write the below article. A user posted a question, stating that he has been working with a Microsoft Project file, and then recently could no longer open the MPP file. He asked us what he needed to do to reopen this project file successfully. Several of us tried to help the user, but to no avail. It appears that the project file was corrupted, which was why he could no longer open it.

The next day, it dawned on me that Microsoft Project has a built-in “backup” function. When enabled, Microsoft Project will automatically create and maintain a backup copy of each of your projects. For the user in question, perhaps a backup copy of his project would have saved the day. So, allow me to show you how to enable the backup function in Microsoft Project.

Warning: The backup function is for people who only use the Microsoft Project desktop application, and who save their projects as MPP files. The backup function is not for people who use Microsoft Project with Project Online or Microsoft Project Server.

Enabling the Backup Functionality

To enable the backup functionality in Microsoft Project, open any project saved as an MPP file. Click the File tab and then click the Save As tab in the Backstage. On the Save As page, click the Browse button. In the Save As dialog, navigate to the folder from which you opened the MPP file. At the bottom of the Save As dialog, click the Tools pick list button and select the General Options item on the pick list, as shown in Figure 1.

In the Save Options dialog, select the Always create backup checkbox, such as shown in Figure 2. Click the OK button when finished.

In the Save As dialog, click the Save button. When prompted in the Confirm Save As dialog to replace the existing project, click the Yes button.

After completing the above steps, Microsoft Project will automatically create a backup file of the saved project file in the same folder as the original project file. The backup file has the same name as the project, except with the file extension .BAK. The software will update the backup file every time you save your project, so that you always have a current copy of the project information in the backup file.

To see the backup file, launch the File Explorer application and then navigate to the folder where you save your Microsoft Project files. In that folder, look for any project that has the .BAK file extension. For example, notice in Figure 3 that my original project file is named Project Navigation 2019.mpp, while the automatically created backup file is named Project Navigation 2019.BAK.

Opening a Backed Up Project

Suppose that you attempt to open your original project file, but that Microsoft Project can no longer open the file because it has become corrupted. In a situation like this, you should try to open the backup file. To do this, click the File tab and then click the Open tab in the Backstage. On the Open page, click the Browse button.

In the Open dialog, navigate to the folder where you store your projects and their accompanying backed up projects. In the lower right corner of the Open dialog, click the file type pick list, which displays Projects (*.mpp) as the default file type, and then select the All Files (*.*) option. In the Open dialog, you will now see the backup project, such as shown in Figure 4. Select the backup copy of your project file and then click the Open button. From there you can click the File tab and click the Save As tab in the Backstage, and save the backed up project file as an MPP file in place of the corrupted project.