Wierd Mac problem

• Mac OS X can't start new programs, or shut down. Long explanation follows. I periodically encounter a very odd problem on my Panther iBook whereby I will suddenly lose the ability to start any new programs. The problem occurs infrequently, and intermittantly. Customarily, I will be working normally and will attempt to launch a new program from the dock. My first sign of trouble is that the application icon continues to bounce for an abnormally long time, and will simply continue to bounce for about a minute, then just stop. End result, no program. I find that once I've encountered this condition, I am completely unable to start any new programs. From that point on its Click, Bounce, Wait, Nothing. Currently running programs appear to operate correctly. All running programs can be shut down, but if I try to shutdown or log off, I only end up with a bare desktop. I can never get back to the login screen, and to shut the machine all the way down, I have to hold the power button down for 5 - 7 seconds to do a hardware reset. I'm guessing the shutdown problems must be due to the fact that the underlying Unix layer needs to run something like "shutdown", but can't because of the original problem. Initially, I figured I simply had a problem with the current session and that a reboot would fix it, but no dice. I then hypothesized that the abnormal shutdown might be contributing to the problem, so when I was forced to do a power reset, I would bring the machine back up, log in, and then immediately log out again in a healthy fashion. Next time I brought the machine up, I'd run into the same problem, no new programs. After dealing with this sort of thing for about an hour, I'll just become too frustrated to carry on any further and will shut the machine down and put it aside for a few days. The next time I come back, no troubles at all. I can go weeks or months (this is secondary machine, and I don't use it daily) without encountering this problem at all, but once it does occur, I'm hosed for the rest of the day. The best that I can figure from going through this 10 or 15 times is that at some point, my system just won't create any new processes. That is the only way that I can explain why running programs work, but newly launched programs never actually come to life. This has got me completely mystified. I've posted queries about this at Apple and at MacOSXHints, but gotten no meaningful responses. I'm hoping some other Mac owner out there has at least seen this before and confirm that I'm not alone in seeing this weird behavior.

• Answer:

  My guess is a hardware glitch somewhere. Not being able to shutdown properly might be due to not being able to star the 'shutdown' process. What happens if you try to run an app from the terminal?