Sudden shutdown

I have suddenly come up with a worrisome problem. While working on various activities a gray curtain starts at the top of the screen and sweeps to the bottom and a message appears - You must restart your computer - hold the power button until it turns off and restart (or words to that effect). It has now happened 3 times in a week. I think all 3 times I was engaged in various activities on the internet. Once restarted it acts perfectly normal until the next episode. Does this ring any bells with anyone?

Thank you

poppi

Sounds like the computer is experiencing kernel panics. If when the gray curtain comes down & you see a message in multiple languages (like the photo below)...definitely a kernel panic.

If this is the case...have you done anything to the computer recently...like a hardware or RAM upgrade?

It would also be helpful to know the exact specs of the computer in question...and the OS version its running (if this info is placed in your profile...we don't have to ask for it).



- Nick

That is exactly what I seee when the problem occurs. No I have not done any hardware or RAM upgrades. iMac 8.1, OS 10.6.8, 2.4 GHz Intel Core 2 duo

Thank you

poppi

Hi poppi

Everymac suggests that your iMac was an early 2008 build and may have shipped with 10.5.x or just possibly 10.6.x.

Do you still have the original Snow Leopard (SL) disks because you could use them to boot from, and carry out an Internal HD verification & Repair.

In the absence of any recent changes by you, these Kernel Panics may reflect a dying HD.

I hope you do anyway, but use the time now to backup your HD.

Ian

IWT said:

Hi poppi

Everymac suggests that your iMac was an early 2008 build and may have shipped with 10.5.x or just possibly 10.6.x.

Do you still have the original Snow Leopard (SL) disks because you could use them to boot from, and carry out an Internal HD verification & Repair.

In the absence of any recent changes by you, these Kernel Panics may reflect a dying HD.

I hope you do anyway, but use the time now to backup your HD.

Ian

Click to expand...

Thank you Ian

I do have the original snow Leopard disk. It is at 10.6.3 but I assume the online automatic update would bring it up to 10.6.8???

I am not that knowledgeable so how do I boot from that disk and "carry out an internal HD verification and repair"?

I copied and pasted into Word the error report that appeared when I restarted the Mac (5 pages long). Are there any special clues I should be looking for in it? Would it help if I attached it to another message?

By the way I had my 4th shutdown message this morning. When it occurred I was away from the Mac and had a spreadsheet open in Excel.

Thanks for your help

poppi

No the version will stay the same poppi as you cannot burn to that disc. If it is the original system install DVD that came with the iMac when it was new, it is the correct disc. Pop the DVD in, reboot and hold down 'C' immediately after the chime until the gear wheel starts and release. When it opens, go to Utilities > Disk Utility > Repair Disk. To attach an error report, go into Console in Utilities, copy the report and paste it. Do you recall if you were in Excel or any other Office program, or just random?

harryb2448 said:

No the version will stay the same poppi as you cannot burn to that disc. If it is the original system install DVD that came with the iMac when it was new, it is the correct disc. Pop the DVD in, reboot and hold down 'C' immediately after the chime until the gear wheel starts and release. When it opens, go to Utilities > Disk Utility > Repair Disk. To attach an error report, go into Console in Utilities, copy the report and paste it. Do you recall if you were in Excel or any other Office program, or just random?

Click to expand...

Apparently I have done something wrong. Followed your instructions but it went through a 45 minute loading and ended up at 10.6.3. Fixed that with an on line update and am now back to 10.6.8. Did disk utility but 'Repair disk' was grayed out so I did 'Verify disk' and it said the HD is Ok.

Confused

poppi

Apparently I have done something wrong.

Click to expand...

It sounds like you just did a re-install and update of OS X 10.6.x. Hopefully all your user data is still intact and working.

Now that that's done, you need to run the Apple Hardware Test:
How to use Apple Hardware Test on your Mac
https://support.apple.com/en-ca/HT201257
and/or
http://osxdaily.com/2016/06/25/how-to-use-apple-hardware-test-to-diagnose-mac-problems/






- Patrick
======

poppi said:

Apparently I have done something wrong. Followed your instructions but it went through a 45 minute loading and ended up at 10.6.3. Fixed that with an on line update and am now back to 10.6.8. Did disk utility but 'Repair disk' was grayed out so I did 'Verify disk' and it said the HD is Ok.

Confused poppi

Click to expand...

You need to boot from your Snow Leopard DVD in order to run Disk Utility and check/do any repairs to the hard drive or files and folders. You can not repair a disk that you're booted from which is why you can only verify it.

Of course if DU in a normal boot says everything's OK with a "Verify", there's no real reason to do the "Repair" when booted from another volume.

PS: What's the "normal" time you Texans go to bed down there???






- Patrick
======

PS: What's the "normal" time you Texans go to bed down there???

Click to expand...

Depends on my day. Sometimes I'm up late when things are quiet and I can get work done. Also, I have to stay up late to keep an eye on the folks who are posting from Pacific Time. ;D

If the KPs continue, I suggest following chscag's suggestion. Something has to be causing them and better to begin with Repair Disk when booted from your Snow Leopard disc. I don't trust verify that much.

Been a while since I last communicated but my problem, if anything, is worse than ever. I now know it is called kernel panic. Frequently I get up in the morning to find the Mac is shut down. To restart it I have to unplug and reconnect the power cord and then press the power button. Other times when working on the Mac I get the message to shut down and restart. In those cases I don't need to unplug. Pressing the power button restarts it.

I have tried several of the suggestions made by y'all. The latest I finally figured out how to access the Apple Hardware Test. I selected the "Perform Extended Test" which took 71 minutes. The result was "No trouble found" so I assume all the hardware is OK???

I have two external hard drives (which I disconnected for the hardware test). One is for iPhoto and iMovie, the other is for Time Machine. Is there any possibility one of those is the culprit? Would it be advisable to disconnect each of those one at a time to see if the problem disappears? Or are there other suggestions I can try?

Appreciate any ideas

Thank you

poppi

Yes. Leave them unconnected for a few days and see what happens.

OK - I disconnected and turned off both EHDs and the left Mac on. 22 hours later I got the message to shut down and restart. That left my Fitbit dongle as the only external plug in (other than mouse and keyboard). I removed the dongle and got a shutdown message 6 hours later. Does that rule out all external hardware? It appears form the hardware test that the Mac is OK. Does that leave software as the suspect?

Thank you

poppi

Everything is suspect on a machine that old. The Apple Hardware Test is not perfect and overlooks many things which could be causing the kernel panics. To eliminate the possibility of software causing the kernel panics, boot the iMac to safe mode and run it that way for a day or so to see if it panics. Do you know how to boot to safe mode? Hold down the shift key as soon as you hear the boot chime and keep holding it until the Apple appears. It will boot very slow that way and when it finally boots, you will have no sound or third party start up programs. Also, all third party drivers will be blocked.

chscag said:

Everything is suspect on a machine that old. The Apple Hardware Test is not perfect and overlooks many things which could be causing the kernel panics. To eliminate the possibility of software causing the kernel panics, boot the iMac to safe mode and run it that way for a day or so to see if it panics. Do you know how to boot to safe mode? Hold down the shift key as soon as you hear the boot chime and keep holding it until the Apple appears. It will boot very slow that way and when it finally boots, you will have no sound or third party start up programs. Also, all third party drivers will be blocked.

Click to expand...

I started to be encouraged as I went a full week without a crash but when I got up this morning the Mac was dead and I had to disconnect/reconnect power before I could restart. Question on the safe start

By "no 3rd party startup programs" does that mean I will not be able to use Mac Mail or the internet?

Thank you

poppi

By "no 3rd party startup programs" does that mean I will not be able to use Mac Mail or the internet?

Click to expand...

Mac Mail and your internet connection via Safari are not 3rd party startup programs. Try safe mode for a while to see what happens, but like I stated above, your machine is old and there could also be hardware problems. However, it's better to eliminate software first before getting into trouble shooting the hardware.

chscag said:

Mac Mail and your internet connection via Safari are not 3rd party startup programs. Try safe mode for a while to see what happens, but like I stated above, your machine is old and there could also be hardware problems. However, it's better to eliminate software first before getting into trouble shooting the hardware.

Click to expand...

OK followed your suggestion and rebooted in safe mode back on April 12. Went a full week with no panics so last night I rebooted in normal mode. Now 17 hours in with no panics (YET). By the way my Mac is on 24/7.

Some comments about safe mode:

As you said there is no sound.

Screen saver uses iPhoto (on EHD) and I get a message "Cannot use with this version of O/S". Works fine on return to normal

Double click on pictures in iPhoto opens a black screen but I can add pix to the file. All works OK on return to normal

Search (command F) does not work in safe mode

Search does not work in mac mail

Mail and Safari do work normal in safe mode

Questions:

What are third party programs? Not Safari?

Does the week without a panic in safe mode mean the hardware is OK? I think I said in an earlier post that the Mac store replaced virtually every hardware item a year ago in an inept attempt to solve a minor problem so this iMac is basically brand new.

If not hardware does that point to software as the culprit? If so how do I try to identify the villain?

As always advice is greatly appreciated

Thank you

poppi

UPDATE

After returning to normal mode the Mac had a panic shutdown within 2 hours. Had to unplug power before I could restart

poppi

No Safari is not an app it ispart of theboperating system. Apps are things you add on to thew operating systems, games, utilities, music etc. Running in safe mode confirms it is something that is precluded from running and it could well be just waiting to commence its little joys when you leave safe mode.

What apps have you added and one assumes youare still running thatv old Snow Leopard?