Configuration:
Guitar Pro 7.6
Windows OS
Symptoms:
Guitar Pro 7.6 displays square blocks instead of beautiful musical notes, it might look like the pic below and of course this is not expected.
Solution:
The Guitar Pro 7.6 fonts have not been installed properly, this might be due to some of your security settings.
To fix this issue, simply download the Guitar Pro 7 fonts and install them manually.
Install font on Mac
Install font on Windows