My computer is giving me the old "question mark folder" at startup for about 15 seconds before OS X kicks in. What's causing this and how can I stop it?
The question mark is a sign of the Mac can not find the Startup drive right away. Open System Preferences->Startup Disk and select your Startup disk. Next do the old reliable "Repair Permissions" (/Applications/Utilities/Disk Utility). Then do these steps to try to "fix" your hard drive with a built in "Unix" fix it program:
2. At the first prompt type these word exactly: /sbin/fsck -fy.
3. Wait for the words saying something like: ** The volume (name_of_volume) appears to be OK. If the words say something like "***** FILE SYSTEM WAS MODIFIED *****", then rerun the commmand fsck againm until the message says everything is good.
4. To get out of single-user mode just type: reboot
Also download the maintenance program Yasu and run all of its routines. This should be done with this or a similar program about once every two months. This will keep OS X running in tip-top shape.
Please report back in none of this helps. Good Luck.