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@Dustin. Yes, I purchased an upgrade to PD12. This was one of those frustrating problems which I just couldn't get past and then it resolved...
Further information on this issue: I was previously running the latest version of PD 12 - Version 12.0.1 (41296). I have PD12 through an upgrade...
I am running Parallels Desktop 12 and would like to use the included offer: "Your purchase includes 1-year 500 GB Acronis Online Backup Service....