Recently I have begun to have a major problem with Tiger in which on a regular basis as I am opening Logic 7.0 Express, I get the "You must Restart Your Computer" screen. It only happens when I am first opening the program, not after it has already loaded. I went ahead and stopped using any audio units that did not pass the compatibility test thinking that must be it, but the problem has stayed fairly regular. I have never heard of this bug coming up before on these forums, but if someone has already discussed or understands the problem, please link me to that posting. As far as any other circumstances, I run a 1.6ghz Power Mac G5 that I keep in very good condition with minimal HD usage, regular permission repair and cache maintenance, etc. All the audio units that I am currently using with Logic are ones that never gave any trouble at all with Os 10.3. Since upgrading to Tiger I have found that most of the problems that I had with 10.3 (frequent programs crashing, Safari bugs) have for the most part gone away while Safari still crashes from time to time. Also I went ahead and downloaded updated Tiger drivers for all of my MIDI controllers, interface, etc. I just can't seem to figure out what is causing this problem. If it is a bug apparent in Tiger than that would be a real shame. I am sick of the amount of garbage that I have to fix on my computer already, having logic be messed up would really be a total pain. Any replies are welcome. Thanks for any help.