Help! Unable to boot into Mac after installing Windows 7

[Dataexar]

I installed Windows 7 on my 2011 27" iMac (running lion 10.7.2)yesterday, before that, I can boot into Mac OS. I installed Windows 7 on a different volume on the same hard disk as the Mac OS.

Now when I turn on my computer, white screen appears, then a apple logo with a progress bar. The process bar will only load 20% for while then disappear, a spinning wheel show up (not the rainbow wheel), it just keep spinning

I tried resetting the SMC, NVRAM, didn't work. I can't repair the Macintosh HD in disk utility, it saids theres a problem. Help!

-John

 

[simsaladimbamba]

What is the problem stated in Disk Utility?

Have you tried any of these steps too?

Mac doesn't boot

Resolve startup issues and perform disk maintenance with Disk Utility and fsck

Troubleshooting: My computer won't turn on

A flashing question mark appears when you start your Mac​