If the font displays as Calibri, it's either not installed correctly, or it's a format that PowerPoint can't read. For best results, stick with Adobe's own font settings. It's important that your system meets the following minimum specifications: A Windows 7 machine with a 64-bit CPU. If your hardware doesn't meet the requirements, we recommend you try to upgrade, or use the alternative operating system. If you are using Microsoft Office 365, be sure to switch to this option if your system is too old. A 64-bit Windows 7 machine. Microsoft Office 2023 installation fails with “An error occurred while upgrading your version of Office. Please click OK to continue. Error Message: An error occurred while upgrading an older version of Office. An upgrade may be necessary.