I have both Windows XP and OSX (default) dual booting - both which worked flawlessly for weeks (press F8 to switch between each).

After installing Kaspersky AntiVirus in Windows, booting into OSX right after now gets me the no entry symbol during the grey boot up screen. Windows still boots up fine.

It can't be random, did the antivirus program kill my osx? Is it even possible? and how to fix?



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A virus can potentially access and damage your harddisk's partition table.

Do you have Macdrive or such software installed on your XP partition ?
If yes, Kaspersky could have probably scanned the Macdrive's mounted OS X partition and messed with it.

Try to boot from your OS X DVD and check your HDD with Disk Utility.

Yes, I do have Macdrive installed on the Windows partition. I will do the disk utility check.

Thanks.

Try in OSX partition to repair your files permission.