Nero is burning or not?

Is there a way to know if Nero is burning a CD/DVD without using the OnDoneBurn event? I can’t use the event so i cannot use a flag variable… the goal is to avoid the start of two or more burning processes at the same time.

No there is no way. The proper procedure is to always wait on the appropriate event before attempting to start another operation. Even if you attempt to start two burning operations, you will receive a COMException telling you that you cannot do this until the previous operation finishes.