As a Mac consultant, I deal with a variety of customers. The software programs I support range from the very old and eclectic to the most up-to-date applications.
Not too long ago when PowerPC processors reigned supreme at Apple, it was common for customers to run Windows on a Mac using Virtual PC. A large percentage of customers stuck with their original versions while others updated their program every time Connectix or Microsoft issued a new release. I could support both sets of customers from one computer, as I could keep different versions of Virtual PC on my Mac and switch whenever the need arose.
Not so with Parallels Desktop 4 or 5. If you run Parallels Desktop 3 (as I do to support my Windows XP customers), you are not allowed to keep this version on your Mac in addition to the later release. During setup, Parallels Desktop 4 or 5 erases version 3 from your system.
A client of mine is a QuickBooks consultant who provides bookkeeping services for both Mac and Windows users. She has installation discs for all of the Mac and Windows versions of QuickBooks that Intuit has produced in recent years. She runs different versions of QuickBooks for Windows on her Mac laptop using VMware Fusion.
Why, I ask, does Parallels prevent consultants like myself from maintaining two or more versions of their program on a single machine when I’ve purchased separate licenses?