Really lost here. Bought a used 10.7.4 equipped Mac Pro. QT either hangs or gives a -1712 error. Tried to find preferences to trash and I cannot find QT preferences or users Library. Have I been in the old Leopard world too long?
Still getting used to Lion but it got progressively worse to where it was opening nothing and crashing. I found that Lion has a built in recovery disk which allowed me to rebuild permissions and running that Quicktime, was back to normal