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I'm on a Mac OS 10.10.3, the installer downloads okay, but then quits after I hit the update button. I'm running it off an internal SSD drive, on an I-Mac 27, with a 7-core processor. I've read the other post, but I'm not on a PC.
It looks like you tried the automatic process from within X-Plane. I did not have an issue with that, but please try updating by downloading the latest installer from X-Plane.com and using that to update instead.
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