Here's my experience...
If you have two machines, (In my case one laptop and one desktop) on the same network, and you're running one instance of FCP, you can't run, or even install a second copy on a machine on the same network. I had taken the laptop to the office studio to upgrade to FCS2. Once I shut down FCP on the office machine, it let me install FCS on the laptop.
Travis
VoiceOver Guy and Entertainment Technology Enthusiast
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