Installation on Mac OSX and Windows 10

The latest version of the software is always available directly on the official website:

Your software can be activated from the menu License Upgrade - License Registration

The entire licence text should be pasted there.

Older versions of macOS

WebAcappellaFusion is digitally signed with an Apple certificate for MacOS 10.11 and higher.

This certificate may not be recognised on older versions of MacOS.


If the following message appears:

“WebAcappellaFusion cannot be opened because the identity of the developer cannot be confirmed

Press the Ctrl key while right-clicking and then “open”

See also

Write blocking on Windows 10


If the following message appears in Windows 10:

“Writing error …” when attempting to open a project.

The application is probably blocked by security software