After Installing 7 w/ Boot Camp, can't access Mac Partition


macrumors 6502
Original poster
Feb 16, 2010
I installed Windows 7 with a 20gb partition on my 160gb SSD, but after I turn on my computer the screen just hangs at "grey" for a long time (a min or so), then just boots windows. How do I got back to OSX or am I not seeing something?
Thanks for any help.


macrumors 65816
Feb 4, 2006
BootCamp changes the startup disk to the Windows partition to help with the install of Windows but does not change it back.

When you startup hold the option key and then when you get Mac OS up and running go to System Preferences > Startup Disk click on the Mac OSX disc and the quit system preferences (you don't need to restart for the change to take effect......)

That way the default startup is Mac OS and if you want to boot into Windows just hold the alt key and choose Windows.


macrumors newbie
Sep 29, 2012
NSW Australia
derek1215 -

I found that my MBP always boots up in the OS I last used before shutting down. When Win7 boots up there is a grey diamond in the task bar on the RH side. Click on this and you will be asked if you wish to reboot in Mac OS. Agree to this and you will be rebooted to Mac OS.

In reverse when you want to change from Mac OS to Win7 - click on the Apple icon on the Menu bar at the top of any open program.
Scroll to - System Preferences
- System
- Startup Disk
- click on Bootcamp (Windows) icon
- click on Restart
and click on restart again in the next window

This always works for me.