Reboot Loop

[Ski52]

Don’t know how long ago this started – I usually leave my computers on 24/7 this problem is one of the reasons why. I turned it off a couple of nites ago, and the next morning it got stuck in a reboot loop – Apple logo, time bar just starts to fill and reboot. The only way I could get back in was to reinstall the OS from the Cmd R screen. This has happened twice. Needless to say, I won’t turn it off anytime soon. I have run what little diags that come with OS10.12.3 – no problems found. I run Parallels for Windows and have run it for 3+ years, so I use mostly Win, the Mac side is near factory stock, very little 3rd party software.
What can I do to get the machine back to normal? What diagnostic software should I run to find the problem?
Any help greatly appreciated.

IMac 27 late 2013
3.2gHz I5
OS Sierra 10.12.3
16G Ram
Thanx
Ski

 

[honestone]

Need to know some things:

1. Does everything run fine on the Windows/Parallels partition?

2. Are you making backups of your Mac partition to an external device? And if you are, what software are you using?

3. Have you ever done any disk cleanup/maintenance/repairs (software-related)?

4. Which third party software (besides Parallels) do you have on the Mac partition? And if you "migrated" from a prior OS to Sierra, did you insure to update any such third party software that needed updating in order to be compatible with Sierra?

5. Disk Utility is "OK" for diagnosing issues, etc., but a more robust disk maintenance program like TechTool Pro or Disk Warrior is much better. There are also some excellent freeware programs available, although they are not as "extensive" as Disk Utility, TechTool Pro or Disk Warrior.

6. Except for Parallels, do you have anything else that is critical on the Mac partition?

 

[Ski52]

Thanks for the reply.
Everything on the Win partition seems to be OK.
I use Time Machine, it uses a 350G LaCie external drive. I assume it's current.
I use Dr. Cleaner periodically to clean out the temp files.
I have installed Wondershare Video Converter Ultimate that hasn't been used for 6 - 8 weeks, Google Earth, uTorrent, Malware Bytes, a Brother printer suite, and Repetier Host 3D printer software.
I have nothing critical on the Mac part. If I can figure out how to hook another drive to the Mac, I should be able to backup the Win side. Can I format just the Mac part?
Will look for the disk utilities you mentioned.
Thanx for your help...
Ski

 

[honestone]

You're welcome! Glad to see that there are only a few narrow minded folks (you know who you are!) who do not thank me for my efforts!

All that third party software looks OK. And excellent that you have a backup.

Now, regarding any "initial" disk cleanup/maintenance/repairs, you can do the following:

1. Do as much disk cleanup as possible on your own. Get rid of stuff you no longer need.

2. Download, install, and run the excellent freeware program Onyx, from here:

http://www.titanium.free.fr/onyx.html

Note that there are specific versions for the various versions of the Mac OS. In your case, you need the first one on the list, V3.2.4. Besides all the useful Cleaning/Maintenance tasks, run the Repair Permissions. You most likely need to run that a number of times in order to fully repair all permissions. I can definitely attest to how useful it is, as I depend upon it. I have been using it for a number of years, and it has always performed very, very well!

3. You'll need to run Disk Utility in an "isolated"/external manner. To do that, you'll need to boot to the (hidden) Recovery HD partition, which apparently you have done before. This link describes what is on that partition:

https://support.apple.com/en-us/HT201314

Note the 4th choice on that menu/screen, Disk Utility. Select it, then select First Aid and point to your Mac partition.

After you do all that, let us know what results.

 

[Ski52]

I've done all but the Disk Utility (I've run it twice this week). 6 or 8 of the Onyx routines want me to reboot. I haven't done that yet. When I do, is there another way to get it to boot other than reinstalling the OS? I have a stand-alone Win machine that has a 2TB & 3 X 1TB drives. I can take one of the 1TB drives and find something to clone my current drive as a last resort.
Thanx
Ski

 

[honestone]

So, from what I understand, you did #1, ie, cleaned off as much stuff as possible. Next, you have downloaded and installed Onyx, and started to use its routines. When you launch Onyx, the first thing you are asked is to whether or not Onyx should verify the structure of your boot drive/partition. Did you let it do that?

The next thing to do is to Repair Permissions, which is under the Maintenance tab.

Now, from there, most of the other useful/applicable tasks in Onyx do require a restart of your machine. But apparently that could be an issue.

Also, when you say "I've done all but the Disk Utility (I've run it twice this week)", did you do that via the (hidden) Recovery HD partition? That would be the only way (with your setup) do use the First Aid feature of Disk Utility effectively.

In any event, just do that much with Onyx, ie, let it verify the structure of your disk, and Repair Permissions. Neither of those tasks require a re-boot of your Mac. When the Repair Permissions is done, you can just quit Onyx.

I'm wondering if you could try something else next. Malwarebyes is a very good anti-malware product, but unfortunately it does not pick up/isolate everything. I have Malwarebytes and do run it periodically, but it has not found any issues yet. But recently, I downloaded the excellent anti-virus software ClamXav. You can get it from here:

https://www.clamxav.com/

You can use it in demo mode for 30 days, and that is what I have done. Surprisingly (and happily!), ClamXav found some "virus-related" files on both of my Macs. I have not been having any issues with either of my Macs, but it was still somewhat "disturbing" to see some "bad" files on my machines (two of them were connected with a solid app I use, VueScan. I suspect they came from one of the downloads of updates I have done for that app, which come out frequently). In any event, I have removed them from my Macs.

After doing all that, and especially if any virus-related files were found, it could be time for a more recent Time Machine backup. But, even though Onyx can verify the structure of your disk, I am not sure how "robust" that is. I have a more robust disk maintenance/repair program, TechTool Pro, that I use for checking out my internal drives (SSDs on both of my Macs).

In any event, after doing all that above, see if the issue still occurs. If so, then you could proceed as follows.
Given that you have a backup, you can boot your machine via Command-R, use Disk Utility there to Erase and format the Mac partition, then do a clean, "virgin" installation of OS 10.12.3, and then use Migration Assistant to "migrate"/copy stuff from your Time Machine backup. You then should be able to re-start the iMac as usual. Hopefully that will work.

The (possible) one "caveat" is that whatever is causing your current issues could be on the Time Machine backup. And who knows what that can be? However, if you have nothing critical on your Mac 9except for Parallels, maybe to could just migrate the Apps from that Time Machine backup That will get you Parallels, and your other third-party apps.

 

[Ski52]

I ran Onyx. It did the verification - OK. I ran the permissions routine, it completed OK.
I ran the Disk Utility First Aid prior to both times I reinstalled the OS.
I have been upgrading/running ClamX for some time - it's still running - I'm on a different machine.
Will fill you in later tonight, or tomorrow when this thing finishes...
Thanx for your persistence...
Ski

 

[honestone]

Yeah, for some reason, ClamXav ran rather "quick" on my Mac Mini, scanning the entire 256 SSD, but only had about 78 gig of stuff on it. Yet, for my MacBook Air with a 251 gig SSD, but again with about 78 gig of stuff on it, it took much longer to complete (did find two "virus" files, but related to an app I do not have on it, VueScan. I have that app on my Mac Mini).

Regarding the use of Disk Utility and re-installing the OS, after you ran First Aid, did you Erase and Format the internal disk before installing OS 10.12.3? If you did, did you also "migrate"/copy anything from your Time Machine backup?

 

[Ski52]

ClamX finally finished about 11 last nite. It found 4 minor things that I quarantined. We'll see what that brings. I ran Disk Utility First Aid and it said OK so OI just left it and went on. I'll try to turn this thing off and see what happens a bit later.

 

[honestone]

I assume you ran Disk Utility's First Air feature after you booted to the Recovery HD partition, correct? Also, as I asked before, when you re-installed OS 10.12.3 (apparently you did that twice), did you first have Disk Utility 1) perform First Aid on the drive, and 2) did an Erase and Format of that drive? If you did that, how did you recover Parallels (and other third-party apps that you have)?

If you did do that Erase and Format, then did a clean, "virgin" installation of OS 10.12.3, and then had Migration Assistant "migrate"/copy all your stuff from your most recent Time Machine backup, there could be problematic files/folders somewhere (or in some places) on that backup. Hopefully, that is not the case, as if it is, then short of installing all your additional apps one by one (not sure what that would do for your Windows/Parallels partition), that would have been the next thing to try.

Migration Assistant does allow one to select which "stuff" they want to recover, but I don't know how detailed one can get with that.

Of course, the other unknown is if there is something more seriously wrong, from a hardware perspective. It's too bad you don't have a more robust disk maintenance/repair program like TechTool Pro or Disk Warrior, as either of them can do a better job than Disk Utility's First Aid.

 

[Ski52]

Sorry it took so long to get back - Friday nite - payday (for those of you that still work) - few beers at Ski's house....they finally all left!
At any rate, I'm on a different machine, the Mac is stuck in the death loop again. At the Ctrl R Disk utility menu, I seem to have picked up a third option, maybe I didn't notice it before, I now have an Apple Disk Image/OS X Base System option. The first option is the Apple HHD... Second is my external Backup drive. If I go to the Apple HHD.../MacHD option, it only shows 1 partition of some 235GB. I am considering dumping that, formatting, and reinstalling the OS. I assume I can use the backup to reinstall the Windows stuff...? Unless it's a hidden directory, the Parallels partition doesn't show. I really can't afford to lose the data on the Win part. I do have an external SATA drive housing with 2 1TB drives that is currently hooked to the stand alone Win box. Assuming I can get the Mac to recognize it, what can I use to clone the Mac drive to another 1TB drive? To get to that point, the only way I have at the moment, is to reinstall the OS.
If this were a Windows machine, I would say fdisk and lo-level format to correct/reallocate the boot sector, but it's not. Many years ago I worked for Sun Micro, and was familiar with Unix, and could probably have accomplished this all a few days ago - but as I said 'for those of you that still work'... I retired some 18 months ago.
I will set it to reinstall everything, and start over tomorrow.
Thanx for hangin' in
Ski

 

[Ski52]

This is getting frustrating! I managed to clone the Mac HD to another 1TB clean drive using Carbon Copy. Finally figured out how to set the external drive to boot and..... same problem. Being I have a copy, I am in the process of erasing and reinstalling a new copy of the OS on the external drive. If I can get it to boot, that will show the problem is software related - I can probably work from there.
More later....