mach kernel - what is it?

Ok im still having trouble starting up my MacBook Pro (Intel). I performed the 10.4.11 update and now i cant get beyond the grey screen, Apple logo and spinning wheel. Ive used target mode to copy some essential files to another Mac as a sort of backup. However, i found something called mach_kernel in the harddrive folder (ie next to where you see the applications folder, library folder, system folder etc).

Could this be causing any startup issues?

Thanks

If you have inadvertantly dragged the kernel out of the system area, I rather doubt your Mac can boot, which would seem consistent with what you report. The kernel is the very heart and soul of the OS - it is the part that does all the magic real time task management. If Mac OS X could be analogized as a body, the kernel would be its brain.

You need to move the kernel back to where it belongs and then you will likely be able to boot. Unfortunately, I am not at my Mac and so cannot tell you exactly where that is. Can some other kind soul chime in with the correct folder for the kernel to be in?

BTW, since your machine does not boot, you will need to boot it off the install disc to get it running so that you can move the kernel file.

Hmmm... I am at my Mac now and did a spotlight search on mach_kernel. It wasn't found. This article from Apple's web site:

http://docs.info.apple.com/article.html?artnum=106805

suggests that it is an invisible file that belongs in the root level of your Macintosh HD. From what you are saying, that is just where it is, so my line of thought here may have been a red herring. Sorry for the needless romp through OS-land. It doesn't explain why you can see it (it is supposed to be a protected invisible file) but it does belong in the root folder, so it presence there is not a sign that anything is wrong.

Ok thanks for the reply mac57. Again, help is much appreciated!

Still cant get this thing to boot - Apple told me i'll have to send it away for repairs which quite frankly is a joke. I've had the machine maybe 6 months tops. Not happy with Apple right now

What I would do at point it put in your install DVD and when you get to the installer screen, select Archive and Install. That will preserve all your files and settings. It will also do an archive of your old system. Then install the 10.4.11 update again when you are done.

Ok im gonna try that. I dont like the thought of my poor old Mac being sent far far away. Thanks again for everyones help

first of all boot from the installation dvd and try to do a disk repair and permissions repair...might save you the 15 mins of archive and restore