error 0xc00000e9 when installing windows 7 on OSX lion

No downgrade, what you need to do is head to Bootcamp and delete the Bootcamp partition

Then head to Disk Utility and Erase Free Space with Zero. this will take some time and write zeros' to all your spare space on the drive, it also reads those zeros back to confirm and when it can't do that the driver software will map off the problem sector on your drive.

Once that's finished, use the Bootcamp software again and Windows should install.

You should learn about Carbon Copy Cloner and WinClone so you can restore OS X or Windows

https://discussions.apple.com/docs/DOC-3045

also read this, if your not going to be using Windows heavily or for 3D games, then this might be a better solution that dual booting.

https://discussions.apple.com/docs/DOC-3321

https://discussions.apple.com/community/notebooks/macbook_pro?view=documents

I have the very same problem, and I did what ds store told, but nothing changed. Could anyone please help? I'm getting desperate. 😕

Seems like no answer. So, I'll bump this with this reply.

I, too, am trying to install Windows 7 on my 2010 Mac Mini.

After the restart, the Black, DOS-like screen does the "Windows Loading" progress ... then ... CRUNK!

Error: 0xc00000e9

Unexpected I/O Error happened.

I've tried this 3 times now -- and just gave up, and came here to see advice.

My next attempt with be (1) verifying my HD, and then (2) creating bootable install USB from the CD, as maybe the SuperDrive is wacky (?)

- joe

Did anyone find a solution???

You are resurrecting a 3 year old thread. I suggest you start your own thread where you describe your problem and system in detail. If you have a problem installing Windows using Boot Camp, post your issue in the Boot Camp Community.