A Microsoft online analytical data engine used in decision support and business analytics, providing the analytical data for business reports and client applications such as Power BI, Excel, Reporting Services reports, and other data visualization tools.
I found the solution to this myself. I don't know why or how this issue began initially, but I right-clicked on Model.bim, went to its properties, and then switched the Integrated Workspace Mode from True to False, and then back to True. I was able to open the Model again.