Disk Utility not finding disks

Question

So, I installed Sierra a few months ago and have had sporadic start up issues ever since - usually requiring me to turn off my Mac and restart in safe mode, then restart the Mac normally.  This has usually fixed the problem...for a while.  After a couple of updates to where I am now (Sierra 10.12.3) it seemed to settle down and start up fine each time...until last week.  Back to restarting in safe mode, running Disk Utility, then a normal restart.This morning, my Mac just hung with an empty status bar and would not boot up.  I shut it down, restarted in safe mode (which took longer this time), and tried running Disk Utility...which just sat there with a spinning wheel, not seeing any disks, not even my hard drive.  So, I normally restarted the Mac, and it booted up.However!  When I try to run Disk Utility, it still sits there and spins the wheel (not the beach ball, but the spinning wheel) and doesn&#x27;t seem to find any disks.Any valid ideas or knowledge of what&#x27;s going on?Did I mention that I never had a boot up problem before upgrading to Sierra (from Mountain Lion)?  Never.  Not once.

tedfrombrunswick · Answer

Hi Jimmy,Thanks for the suggestions.I contacted Apple chat and it was suggested that I reboot in Recovery mode, then run Disk Utility.  I did that and it found my hard drive.  I ran DU and it showed everything was fine.  So, I rebooted my Mac normally and ran DU.  It then recognized my drive, so again I ran DU and no issues were reported.Then, I ran EtreCheck and found the following (below) in the SMART report for my hard drive.  If you scroll down to the Vendor Specific SMART Attributes with Thresholds: section, the words Pre-fail and Old-age appear on several lines under the TYPE column (sorry, the formatting didn&#x27;t transfer here).  Does this mean that my hard drive is about to fail?  If so, it&#x27;s interesting that Disk Utility doesn&#x27;t show any kind of warning about impending hard drive failure.smartctl 6.5 2016-05-07 r4318 [Darwin 16.4.0 x86_64] (local build)Copyright (C) 2002-16, Bruce Allen, Christian Franke, www.smartmontools.org&#x3D;&#x3D;&#x3D; START OF INFORMATION SECTION &#x3D;&#x3D;&#x3D;Device Model:     APPLE HDD HTS541010A9E662Serial Number:    J580001MHDMXHALU WWN Device Id: 5 000cca 6c6d3d6bbFirmware Version: JA0AB560User Capacity:    1,000,204,886,016 bytes [1.00 TB]Sector Sizes:     512 bytes logical, 4096 bytes physicalRotation Rate:    5400 rpmForm Factor:      2.5 inchesDevice is:        Not in smartctl database [for details use: -P showall]ATA Version is:   ATA8-ACS T13/1699-D revision 6SATA Version is:  SATA 2.6, 3.0 Gb/s (current: 3.0 Gb/s)Local Time is:    Fri Feb  3 15:32:21 2017 ESTSMART support is: Available - device has SMART capability.SMART support is: Enabled&#x3D;&#x3D;&#x3D; START OF READ SMART DATA SECTION &#x3D;&#x3D;&#x3D;SMART overall-health self-assessment test result: PASSEDGeneral SMART Values:Offline data collection status:  (0x00) Offline data collection activity  was never started.  Auto Offline Data Collection: Disabled.Self-test execution status:      (   0) The previous self-test routine completed  without error or no self-test has ever   been run.Total time to complete Offline data collection: (   45) seconds.Offline data collectioncapabilities:  (0x5b) SMART execute Offline immediate.  Auto Offline data collection on/off support.  Suspend Offline collection upon new  command.  Offline surface scan supported.  Self-test supported.  No Conveyance Self-test supported.  Selective Self-test supported.SMART capabilities:            (0x0003) Saves SMART data before entering  power-saving mode.  Supports SMART auto save timer.Error logging capability:        (0x01) Error logging supported.  General Purpose Logging supported.Short self-test routine recommended polling time:  (   2) minutes.Extended self-test routinerecommended polling time:  ( 210) minutes.SCT capabilities:        (0x003d) SCT Status supported.  SCT Error Recovery Control supported.  SCT Feature Control supported.  SCT Data Table supported.SMART Attributes Data Structure revision number: 16Vendor Specific SMART Attributes with Thresholds:ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE      UPDATED  WHEN_FAILED RAW_VALUE  1 Raw_Read_Error_Rate     0x000b   100   100   062    Pre-fail  Always       -       0  2 Throughput_Performance  0x0005   100   100   040    Pre-fail  Offline      -       0  3 Spin_Up_Time            0x0007   176   176   033    Pre-fail  Always       -       1  4 Start_Stop_Count        0x0012   093   093   000    Old_age   Always       -       11583  5 Reallocated_Sector_Ct   0x0033   100   100   005    Pre-fail  Always       -       0  7 Seek_Error_Rate         0x000b   100   100   067    Pre-fail  Always       -       0  8 Seek_Time_Performance   0x0005   100   100   040    Pre-fail  Offline      -       0  9 Power_On_Hours          0x0012   086   086   000    Old_age   Always       -       6208 10 Spin_Retry_Count        0x0013   100   100   060    Pre-fail  Always       -       0 12 Power_Cycle_Count       0x0032   093   093   000    Old_age   Always       -       11582160 Unknown_Attribute       0x0032   100   100   000    Old_age   Always       -       0191 G-Sense_Error_Rate      0x000a   100   100   000    Old_age   Always       -       0192 Power-Off_Retract_Count 0x0032   100   100   000    Old_age   Always       -       37193 Load_Cycle_Count        0x0012   051   051   000    Old_age   Always       -       490238194 Temperature_Celsius     0x0002   176   176   000    Old_age   Always       -       34 (Min/Max 16/48)195 Hardware_ECC_Recovered  0x000a   100   100   000    Old_age   Always       -       0196 Reallocated_Event_Count 0x0032   100   100   000    Old_age   Always       -       0197 Current_Pending_Sector  0x0022   100   100   000    Old_age   Always       -       8198 Offline_Uncorrectable   0x0008   100   100   000    Old_age   Offline      -       0199 UDMA_CRC_Error_Count    0x000a   200   200   000    Old_age   Always       -       0223 Load_Retry_Count        0x000a   100   100   000    Old_age   Always       -       0254 Free_Fall_Sensor        0x0032   100   100   000    Old_age   Always       -       20SMART Error Log Version: 1No Errors LoggedSMART Self-test log structure revision number 1No self-tests have been logged.  [To run self-tests, use: smartctl -t]SMART Selective self-test log data structure revision number 1 SPAN  MIN_LBA  MAX_LBA  CURRENT_TEST_STATUS    1        0        0  Not_testing    2        0        0  Not_testing    3        0        0  Not_testing    4        0        0  Not_testing    5        0        0  Not_testingSelective self-test flags (0x0):  After scanning selected spans, do NOT read-scan remainder of disk.If Selective self-test is pending on power-up, resume after 0 minute delay.

JimmyCMPIT · Answer

Shut downdisconnect all external devices except OEM keyboard and mousereboot into safe modeTry safe mode if your Mac doesn&#x27;t finish starting up - Apple SupportOpen Disk Utility If the issue continues your HD may be failing, this is very common and drive makers include a theoretical date of failure under normal use with every device they manufacture. If the utility works it could be another device connected to the system. If so identify it and replace it if it has failed.