how can i change my system version in recoverymode

You might want to start your own post. A new post would be much more visible. You can link to this one. Please state what your problem is.

What is the exact error message when try to reinstall? You can't install 10.5.5 from a Recovery Partition. It has to be installed from a DVD.

• I have the exact same problem.
• Am (was!) running 10.10.5 on a macbook Pro.
• Wanted to install ProTools 9.
• Received a message "ProTools requires 10.5.5 to operate" that is actually a paraphrase, but close.
• In a fit of genius decided to change the data, located at ~System/Library/CoreServices/SystemVersion.plist,

from 10.10.3 to 10.5.5 ........ I think the term is "brick".....

• The machine would not boot, so I went through recovery partition (command R) to re-install OS.
• The OS will not install because (again, I paraphrase) the current OS (10.5.5) is too old to update.
• Owing to the fact that my genius only arrives in fits, much like whooping cough or the flailings of a super annoying child, I have no idea how to get back to square one.
• This is of course clearly not my fault because what I did makes complete sense, especially in hindsite, and the warning about using "sudo" was only inserted by some coder to scare off lesser men than myself..

  youngfrommemphis wrote:

  
  

  I Was running 10.11.6 I changed it to 10.7.6 now when I try to open apps it says I need os 10.11.6 to run. was installing pro tools 10.3.9. Since I cannot access apps I can not change it back. Thanks for all your help

According to your profile, you are on 10.11.6; what is it that you are trying to accomplish?

Please be exact and also post your Mac model/year.

You need to tell us a lot more for someone to be able to help effectively:

So what OS version were you on before being told to change it?

Which version are you on now?

What Pro Tools (there are different ones)?

What gave you the message (Pro Tools installer or Mac OS?) and exactly what did it say?

Did it tell you to change the version of the Mac OS or pro tools?

Are you saying you can't even access built-in apps like Finder? If that's the case, you're going to have to reinstall OS X.

If you can, then go to /System/Library/CoreServices/SystemVersion.plist, right click on it and select "Open with," and select TextEdit. You should then be able to edit the file to change it back.

Again, if this does not work you have to reinstall OS X per the link I provided.

There was never such a thing as OS X 10.7.6, which is probably why the system got confused.

Restart with the Command and S keys held down and run the following:

mount -uw /

defaults write /System/Library/CoreServices/SystemVersion ProductVersion '10.11.6'

defaults write /System/Library/CoreServices/SystemVersion ProductUserVisibleVersion '10.11.6'

exit

Alternatively, restart to the recovery partition, skip the first and fourth commands, add /Volumes/drivename at the beginning of the paths in the second and third, and single quotes before and after them.

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