Hello Expert.
When I worked with iMac for Some hours it shutdown suddenly, How can I find the root of problem?
Thank you.
1) Check HDD SMART Data. This will check for corruptions on the HDD. You can download and run SMART Utility here:
http://cloudfront.volitans-software.com/smartutility314.zip If there's anything other than 'Passed' is displayed, the HDD is corrupted, and there's the root of your problem.
2) Verify your volume. To do this, open Disk Utility (search for it in Spotlight, or go to Applications>Utilities>Disk Utility). Then single-click your volume (typically called Macintosh HD) to highlight it, and then click the 'Verify Disk' option along the right-hand side. If it comes up with red writing, we'll need to repair the disk. Quote this if that's the case and we'll take you through how to do that.
3) Restart your iMac, with the option 'Reopen windows when logging back in'
disabled. This means that if there's a background software conflict or memory leak causing the problem, it won't come back up.
Highly unlikely to be causing the issue, but worth getting into the habit of doing it.
4) Check for software updates for your OS (Apple menu>Software Update on Mavericks or earlier, or Apple menu>App Store on Yosemite). There may be an update for the OS. Again
highly unlikely to be causing the issue, but it's worth checking.
Other issues causing it could be:
- RAM
- Faulty logic board
- Overheating
So once you've had an opportunity to try the above, please quote this as we can do a number of additional troubleshooting steps on the RAM/MLB/temps if no problems are found.