Boot sector residue - or 'BIOS'?

Nov 19, 2008
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Hi all

A friend asked me to install Windows on his new iMac (27") and there was a problem during the install - memory address error - so I followed the Apple instructions and uninstalled the partition.

Problem is that there is still something there trying to go down the windows
install procedure and on power up a message "... can't find boot disk..." appears.

Am I correct in assuming that there is something like a boot command still "installed" either on the hard drive or in the equivalent of the BIOS?

I can reformat the drive but am not sure that will get rid of the problem.

All advise greatly anticipated!

Ken :(
Mar 2, 2010
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New Zealand
If you hold down the ALT/Option key on powerup it should bring up a list of available voluems to boot from and selecting your OSX volume should allow it to boot normally.
Once in OSX go into the Startup Disk preferences and select the OSX volume as the Startup disk.
If this doesn't work then try powering on while holding down ALT + Command + P + R and wait until the machine has started and bonged at least twice (This usually requires you to have 3 arms, you will see what I mean when you try). This will clear the PRAM. Once this has been done try the first sequence again.

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