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The gateway support site is shutting down and being absorbed into the Acer support site.
To order the official recovery media for your device you need to enter the SNID from you gateway machine on this page and order the disks.
With that being said.. When it gets stuck at 99%. How long have you let it sit there? More then a couple of hours?
Also, have you tried removing disk 3, and reinserting disk 3. Or, removing disk 3 and inserting disk 1 ..
Is there anything you can do when it hits 99% to help wake it up, so it finishes the process?
If not, it may just be a failed recovery disk set. ( in which case the official set will work )
If you get stuck or have further questions, let me know!
I strive to provide great service, and greatly appreciate a rating of excellent ( 5 stars ) selected and submitted below this answer or at the top right of the screen. I always answer follow up questions.Dustin S.Senior Technician and Network Switching Systems Operator / Maintainer.