Hi, need assistance on this puzzling El Capitan upgrade problem.
I have tried 3 times to upgrade from Yosemite to El Capitan. And 3 times I get the same problem.
Generally, El Capitan is downloaded (from App Store) and installed successfully.
That is, once El Capitan is installed, the Mac reboots automatically and I can login properly.
The PROBLEM starts when I reboot Mac. It will get stuck at Apple boot screen, with the progress bar strip 'motionless'.
Fortunately, each time I can Cmd-R to 'Restore from Time Machine' to Yosemite. And thereafter I can work on Yosemite properly.
There is one time I try Reinstall El Capitan (seems to re-download from Internet). But the same problem on 2nd reboot.
Each time of El Capitan upgrade and Yosemite RESTORE has taken me at least 6hrs (!!!).
Now I try again El Capitan upgrade. This time I uninstall Norton Anti-Virus and Soundblaster, as it seems that anti-virus app may cause a problem.
As I am researching on this problem, I DARE NOT reboot the Mac.
Hopefully someone can assist to enlighten me to fix problem.
Following advice from this blog, I run the command:
cd "/Volumes/Macintosh HD" ; ls -1 Library/Extensions/ ; ls -1 Library/Application\ Support/VirtualBox/ ; ls -1 Library/Application\ Support/EltimaSyncMate/ ; find System/Library/Extensions -ctime +1w -depth 2
ACS6x.kext
ATTOCelerityFC8.kext
ATTOExpressSASHBA2.kext
ATTOExpressSASRAID2.kext
ArcMSR.kext
CalDigitHDProDrv.kext
HighPointIOP.kext
HighPointRR.kext
PromiseSTEX.kext
SoftRAID.kext
ls: Library/Application Support/VirtualBox/: No such file or directory
BackService.app