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Leopard Compatibility – Keyboard Lock

We have received reports from a few users of the Apple Operating System, OS 10.5 Leopard, experiencing a problem when they attempt to use POSIM Diamond. We would like to make everyone aware of the problem and possible solutions. This issue is not found within POSIM, but rather with a Mac service known as Rosetta that allows POSIM Diamond to work on the Leopard platform. This issue is not consistent with all computers using Leopard. Very few users have experienced the problem; the vast majorities are able to use the Leopard platform flawlessly and efficiently.


  • The keyboard locks up and is not functional.

What systems has this issue been experienced on?

  • Mac Minis
  • iMac G4, G5, and Intel (both Dual Core and Core Duo)
  • MacBook4
  • MacBook Pro

If I upgrade my computer to Mac OS 10.5, will I experience this problem?

  • At this point, there have been no clear indicators to determine which machines will be affected when upgrading versus which will not. Our best recommendation is to stick with the old adage, “If it ain’t broke, don’t fix it.”
  • If you find that you need to upgrade, we recommend backing up your computer image first.

Is Mac aware of the situation?

  • We have been in contact with Mac developers regarding this; they have acknowledged the bug and are currently working to resolve the issue.

What can I do to alleviate the issue?

  • Many users have found that periodically toggling between screens or clicking off the POSIM screen and back on will fix the situation.
  • Other users have reformatted and re-installed Mac OS 10.4.11 in order to continue using their software.

Are there any issues with downgrading to Tiger (10.4)?

  • If your computer originally came with Tiger (10.4) then all you need is the disc(s) that came with your computer.
  • Computers that were purchased with Leopard we have found are more difficult to downgrade because the Mac hardware and discs are locked to each other. So you will need to find a Tiger disc that is specific to your hardware e.g. Mac Mini, iMac, MacBook etc. The disc will also need to support the type of processor you have either PowerPC or Intel.