ARA is short for Audio Random Access. It’s kind of a plugin format like VST. The difference is that VST works in real time, where ARA plugins are offline (non real time) plugins.
I’ve activated Wavelab 13. having read a bit more, the Elements version ara doesn’t work with Cubase. That’s OK as I’ve never used both together so, i just need to stop Cubase trying to open the Wavelab ara when it starts
ARA extensions are just VST3 files, so you will most likely find the Wavelab one in the VST3 folder. You can simply delete it (but maybe keep a backup).
It has been confirmed that a program error (software bug) is occurring with the release version of Wavelab Elements 13. The ARA Extension is only available for Wavelab Pro 13, but it’s causing this error message with Elements licenses.