Finder restarts every third second - cant use my computer!

Question

Hi
I have a really big problem that makes it impossible for me to use my computer. Since yesterday Finder has been restarting about every third second which makes the icons on the desktop dissapear and appear and also the upper menu is doing the same.
I have a video clip of it so you can see the problem.
http://www.dsmovies.se/ovrigt/problem2.mov
Please help me, I really need to be able to use my computer again.
Really appreaciate all the help I can get.
Thanks

Answer 1

Barney-15E wrote:
There is some info here. Try creating a new user, if possible and log into that. If all is well, there is something wrong with your previous user account. If it still fails, then you've got a system-wide problem.
Third-party Contextual menus sometimes cause this problem. Look in yourUser/Library/Contextual Menu Items/ and move anything to the desktop. Restart and see if that helps. If it does, try placing them back one at a time until you find the culprit.
Good idea but hard to do if you only have 2 or 3 seconds before Finder relaunches.
Try this:
1. Restart computer and hold Command and S. The Command key usually has the Apple logo on it. This will boot you to Single User Mode which will be a black screen with lots of white text.
+Note about Single User Mode and these instructions+: Type everything exactly as instructed (including spaces), keeping letters lowercase or capitals as the appear on screen or in these instructions. In the instructions, when you see <RETURN>, instead of typing it out, you want to press the Return key on your keyboard. In the instructions if you see yourusername then you will need to type your username as you saw it on the screen.
2. Type the following:
mount -uw / <RETURN>
ls /Users <RETURN>
Note: The last command will show a list of the different account folders. Find the one that has your name. This is your username.
cd /Users/yourusername/Library/Preferences <RETURN>
mv com.apple.Finder.plist com.apple.Finder.plist.old <RETURN>
reboot <RETURN>
Note: At this point your computer should restart. Log in how ever you normally do and see if the same thing is happening. If not, stop here. Otherwise repeat step 1 and then go directly to step 3 below.
3. Type the following:
mount -uw / <RETURN>
mv "/Users/yourusername/Library/Contextual Menu Items" "/Users/yourusername/Library/Contextual Menu Items.old" <RETURN>
Note: You may get a message saying the folder doesn't exist. If so, ignore it.
mv "/Library/Contextual Menu Items" "/Library/Contextual Menu Items.old" <RETURN>
reboot <RETURN>
Let the computer restart and things should be working after that.