If your computer's machine ID changes Beat Producer will cease to be authorized and not load or preview anything other than the supplied demo material. This can be the result of changes with your computer's hardware or software. If your license file is in the right place but Beat Producer has stopped working check your machine ID against the one included in the e-mail you were sent with your license file. If your machine ID has changed you simply have to apply for a new license file the usual way. Go back!