I had a couple of MacBook Pro laptops grace my desk and I have been upgrading them to Mac OS X 10.7 (Lion). The first one (maybe eighteen months old) went through without a hitch but the second one (which is a few years old) had all manner of problems including reading my original DVD-RW that I had burnt using the DMG file from the Mac App Store. Another significant problem I encountered was after the initial installation, I kept encountering the error…
“There was a problem installing Mac OS X”.
Quite non-descript and quite unhelpful and even a format and subsequent reinstall didn’t fix the problem.
What I discovered was that the setup for Lion seems to store data in the PRAM (Parameter Random Access Memory) and if this data is corrupted or becomes stale it becomes necessary to reset it in order to undertake a successful installation.
So how is it done?
- Turn off the computer,
- Hold down “Command”, “Option”, “P” and “R” on the keyboard,
- Turn on the computer,
- Keep holding down the keys until the computer restarts itself again (maybe ten or fifteen seconds at most),
- Release the keys after the computer has restarted again.
From here you should be able to proceed with the installation of Lion with no further problems.
18 comments
2 pings
Pino
September 2, 2011 at 02:00 (UTC 10) Link to this comment
Thank you – this helped me
fotomate
September 4, 2011 at 16:31 (UTC 10) Link to this comment
finally it works. i couldn’t get through this error, bit now it works fine on my old MacBook Pro. thanks
Boydo
September 4, 2011 at 17:40 (UTC 10) Link to this comment
Glad to hear! It’s certainly one of the more obscure and frustrating problems encountered with an OS installation.
changyoung
September 7, 2011 at 01:34 (UTC 10) Link to this comment
Oh my god! thank you!
Charly
September 11, 2011 at 13:01 (UTC 10) Link to this comment
Thx for the tip !
Jo
September 20, 2011 at 13:13 (UTC 10) Link to this comment
OMG! You are a life saver. Thank you.
Boydo
September 20, 2011 at 13:48 (UTC 10) Link to this comment
No worries
Elliot F
September 21, 2011 at 04:17 (UTC 10) Link to this comment
The user had re-formatted his HD and couldn’t recover. Nothing else worked. 2 days. The recovery partition, Firewire target disk mode, DVD installer. After clearing the PRAM, installation is going now from a clean install DVD image.
Michael H
December 7, 2011 at 00:14 (UTC 10) Link to this comment
You ROCK! Didn’t know we had a “P” ram still. Thank you Soooooooo much
Boydo
December 7, 2011 at 00:38 (UTC 10) Link to this comment
My pleasure!
Martin
December 20, 2011 at 07:24 (UTC 10) Link to this comment
Thank you so much.
Genius!
Boydo
December 20, 2011 at 10:02 (UTC 10) Link to this comment
Glad to help
Chao
January 3, 2012 at 00:18 (UTC 10) Link to this comment
Great tip, thanks.
gandalf
February 12, 2012 at 02:28 (UTC 10) Link to this comment
saved me, thank you very much!!!!
Dave Kemsley
February 18, 2012 at 18:29 (UTC 10) Link to this comment
There’s one more step to do this for those who have the firmware password turned on: turn it off.
You can’t reset PRAM/NVRAM if the firmware is password protected.
Peter
February 28, 2012 at 21:12 (UTC 10) Link to this comment
Actually PRAM resets the Firmware password, you just have to either change a ram stick or temporarily remove it then reset the PRAM.
Isra V
February 22, 2012 at 13:04 (UTC 10) Link to this comment
Thanks for your help…Regards.
Boris
May 1, 2012 at 08:36 (UTC 10) Link to this comment
Thanx a lot!!!! Respect!)))
Lion in the Living Room « Glog
November 18, 2011 at 05:11 (UTC 10) Link to this comment
[...] Oh well, nothing the Googletron couldn’t take care of. [...]
Slow or Infinitely Long Shutdowns on Mac OS X » Boydo's Tech Talk
April 25, 2012 at 20:50 (UTC 10) Link to this comment
[...] Anyway, if the above hasn’t worked you can also try resetting the PRAM on your Mac by following these instructions. [...]