When installing Finale v26 on a computer that currently has Finale v27 installed, the v26 font installer may remove the SMuFL-based fonts on that system. You will know this is the case if you open or create a SMuFL-based document in Finale v27 and incorrect glyphs are being used for the notation.
The font installer packaged with the v26 installer for Windows is not able to recognize the new SMuFL-based fonts as correct MakeMusic fonts. This will cause the installer to remove these fonts while installing the legacy fonts. This is a known occurrence and can quickly be fixed by downloading and running the MakeMusic font installer attached here.
Once you have completed installing the fonts with stand-alone font installer, restart the system and check that the issue has been resolved.
If this does not correct the issue or you encounter other problems during this process, please use the Submit a request option above to contact Customer Support.