Carl - I moved your thread to the Music Creator forum since this is the more appropriate place to discuss issues with MC7.
I'm afraid, however, we'll need more info. write down exactly what the dialog box says when it pops up before you click OK (and if there's another dialog box after that, tell us what that one says as well). we will need to know what it's telling you before we can really help.
Sorry - I just realized I may have been trigger happy - you said ALSO in MC7, so maybe you meant in Sonar as well. if so, which version of sonar are you running? I'll move it back if we can't help you here.