We see this on occasion. The trick is to simply reset or reinitialize the XBooks add-in. Follow these steps to do so:

  1. Click the File tab, click Options, and then click the Add-Ins category.
  2. In the Manage box, click Excel Add-ins, and then click Go. The Add-Ins dialog box appears.
  3. In the Add-Ins available box, select the check box next to XBooks, and then click OK.

Posted in: XBooks