I've had this problem for possibly 4 months now and it is super annoying! It all started in the middle of Febuary. I started up my mac and up came the flashing folder. So I unplugged my mac and everything worked fine. Maybe a month later the real issue began. I started up the mac and the same thing happened. I unplugged my iMac then plugged it back in and started it up. Same thing. I waited maybe 15 minutes and tried again. Then 30 minutes. Eventually it worked. Almost every time I start up my imac it gives me the folder/question mark, and I sigh to myself, because I know I have to wait like 30 minutes for it to work again. I called apple and they said it was something to do with a corrupt file, but there are none. I even had someone come over and check. This problem is really frusturating! Here is my info: Model Name: iMac Model Identifier: iMac8,1 Processor Name: Intel Core 2 Duo Processor Speed: 2.66 GHz Number Of Processors: 1 Total Number Of Cores: 2 L2 Cache: 6 MB Memory: 2 GB Bus Speed: 1.07 GHz Boot ROM Version: IM81.00C1.B00 SMC Version (system): 1.29f1 Serial Number (system): -cut- Hardware UUID: -cut- System Version: Mac OS X 10.5.8 (9L31a) Kernel Version: Darwin 9.8.0 Boot Volume: Macintosh HD Boot Mode: Normal Computer Name: -cut- User Name: -cut- Time since boot: 10 minutes It's a 10.5.8 Leopard too. I really want help! I also do not have the installation disk, so don't suggest anything about that. Also my mac sometimes freezes when it wakes from sleep or screensaver. That's when i get pissed cause I know I have to wait 30 minutes again and I LOSE ALL MY FRICKEN WORK!!! GAAHH!