I just tried and couldn't get it to work, but this is under High Sierra. I can recall being able to perform a couple tasks like this under Sierra.
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Clean Installation macOS High Sierra shows "Prohibitory Symbol"
- Thread starter deeprathod
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I just tried and couldn't get it to work, but this is under High Sierra. I can recall being able to perform a couple tasks like this under Sierra.
That's really strange! Maybe it's some special behaviour of that particular drive or there is a problem with the internal controller cable. I couldn't find any firmware updates for the drive that could resolve the issue.
If you want to cancel the 8 hours installation, you could boot the USB flash installer, open Disk Utility and reformat the whole EVO SSD with APFS, then quit Disk Utility and start the installation again. Maybe that will be faster. I hope that no other issues will arise due to cancelation of the install.
If you want to cancel the 8 hours installation, you could boot the USB flash installer, open Disk Utility and reformat the whole EVO SSD with APFS, then quit Disk Utility and start the installation again. Maybe that will be faster. I hope that no other issues will arise due to cancelation of the install.
What i now did is, i formatted the disk using AFPS but the SSD is connected via USB and it says 45 minutes now. Lets see how it goes.
What was the reason that you detached the SSD from the internal controller? Didn't reformatting work while it was internally connected? Will you put it back inside before installing the OS?
Because after connecting internally it was showing 8 hours to install. So now, i am going to install via USB and then plug it inn, to see if it works or not as now the format of the disk is AFPS.
It showed up 8 hours for installation on the internal bus while the drive already was AFPS formatted?
Now i have formatted the drive, put the hard disk in the macbook. Default drive is SSD and doesn't show that symbol anymore.
But the main issue now is, its very slow, it taking 15 minutes to open a finder. Damm slow.
Hey, hey, at least a partial success.
Nonetheless, that's not normal and I think it indicates that the real problem is somewhere else. You can reboot while pressing D. That will launch Apple Diagnostics for checking your system.
As the drive is fast as an external USB device and slow on the internal bus, my blind guess is that the hard drive cable is defective. Another indicator for that is that you mentioned many bad blocks on your former drive. To replace the cable take a look at this guide on iFixit.
EDIT: Apple Diagnostics won't tell you about a defective hard drive cable, but if it doesn't report anything else, that's another hint on the cable.
Nonetheless, that's not normal and I think it indicates that the real problem is somewhere else. You can reboot while pressing D. That will launch Apple Diagnostics for checking your system.
As the drive is fast as an external USB device and slow on the internal bus, my blind guess is that the hard drive cable is defective. Another indicator for that is that you mentioned many bad blocks on your former drive. To replace the cable take a look at this guide on iFixit.
EDIT: Apple Diagnostics won't tell you about a defective hard drive cable, but if it doesn't report anything else, that's another hint on the cable.
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Sorry its the same, I restarted again to confirm, its still showing the symbol. And we are back to 0.
The test went perfect, without any issues.
No i by mistakely said about the bad sectors i guess. The normal HDD works perfectly fine.
Well, I won't call it back to 0... You could install the OS and boot up once, even if it was running slowly, correct?
There is a small chance that the SSD is causing the "prohibitory symbol" just on the internal bus, because of some firmware incompatibilities or another failure, but I don't think so. If it's hassle free to give the SSD drive back and get exchange with another one, yeah why not trying this.
I still believe that your disk drive cable is defective.
Finally, if you put the SSD back at the external USB or preferably TB port and it's going to boot without any issues, you could run several disk drive tests with more or less expensive software, but that software is probably more expensive than just buying and exchanging the disk drive cable. Of course I'm not absolute sure if it's really the cable, but that's my best bet. Unfortunately there is no software solution that I'm aware of to attest a cable defect and IMHO it doesn't make much sense to test the SSD with built-in tools like 'diskutil verifyVolume' or 'fsck_apfs' if the error is pointing more to a connector issue.
Here is a writeup from an Apple tech and another user report about exchanging the cable.
Other opinions are very welcome...
There is a small chance that the SSD is causing the "prohibitory symbol" just on the internal bus, because of some firmware incompatibilities or another failure, but I don't think so. If it's hassle free to give the SSD drive back and get exchange with another one, yeah why not trying this.
I still believe that your disk drive cable is defective.
Finally, if you put the SSD back at the external USB or preferably TB port and it's going to boot without any issues, you could run several disk drive tests with more or less expensive software, but that software is probably more expensive than just buying and exchanging the disk drive cable. Of course I'm not absolute sure if it's really the cable, but that's my best bet. Unfortunately there is no software solution that I'm aware of to attest a cable defect and IMHO it doesn't make much sense to test the SSD with built-in tools like 'diskutil verifyVolume' or 'fsck_apfs' if the error is pointing more to a connector issue.
Here is a writeup from an Apple tech and another user report about exchanging the cable.
Other opinions are very welcome...
I know my situation is not quite the same but I've found a couple pics that may shed some light on the situation. The first image shows an error message that popped up towards the end of the process, while installing High Sierra and shows that the preboot volume couldn't be created.
Following this install I had all sorts of problems that were not easily resolved and it just didn't feel right. I eventually booted into recovery mode after various attempts, but found it was impossible to repair the main startup volume where High Sierra had been installed. I can't tell you why, but it wouldn't unmount the drive.
At this point things became really messy and I couldn't even shut down the computer normally, so I eventually forced shutdown on the computer via the power button. The next time I started up I had the same prohibited symbol on the screen.
I left it like that and after several minutes it slowly advanced towards the recovery drive by itself, but this time I was able to repair the SSD in disk utility. Following this I wiped everything and did a clean install. The computer has basically been problem free since then, apart from an initial problem re-importing old email that was resolved after a while.
EDIT: Following the clean install I regained a huge amount of drive space, even after re-installing all the apps.
Following this install I had all sorts of problems that were not easily resolved and it just didn't feel right. I eventually booted into recovery mode after various attempts, but found it was impossible to repair the main startup volume where High Sierra had been installed. I can't tell you why, but it wouldn't unmount the drive.
At this point things became really messy and I couldn't even shut down the computer normally, so I eventually forced shutdown on the computer via the power button. The next time I started up I had the same prohibited symbol on the screen.
I left it like that and after several minutes it slowly advanced towards the recovery drive by itself, but this time I was able to repair the SSD in disk utility. Following this I wiped everything and did a clean install. The computer has basically been problem free since then, apart from an initial problem re-importing old email that was resolved after a while.
EDIT: Following the clean install I regained a huge amount of drive space, even after re-installing all the apps.
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@ashleykaryl It's hard to realise that such a flaky OS installer can pass the beta stage. By the way, there is a hint on tinyapps that makes macOS High Sierra Disk Utility behaving a little better, if you toggle View > Show All Devices.
That could have been one problem we encountered in this thread. While we tried to convert the JHFS+ volume to APFS, we didn't see the nested partition from the parent volume and thus probably weren't able to use the greyed out 'Convert to APFS'.
@deeprathod If the "Prohibitory symbol" is really just because of an installer bug and your hard drive and cable is fine, then there should be at least no problems arising, if installing and running an older macOS while the SSD drive is internally attached. Concerning buggy installers, did you verify the checksum of your latest installer app download, too?
That could have been one problem we encountered in this thread. While we tried to convert the JHFS+ volume to APFS, we didn't see the nested partition from the parent volume and thus probably weren't able to use the greyed out 'Convert to APFS'.
@deeprathod If the "Prohibitory symbol" is really just because of an installer bug and your hard drive and cable is fine, then there should be at least no problems arising, if installing and running an older macOS while the SSD drive is internally attached. Concerning buggy installers, did you verify the checksum of your latest installer app download, too?
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It's worth pointing out that all of this happened for me with the final beta and it was initially a straight upgrade from Sierra, but without doubt, it was the worst upgrade experience since the first release version of OS X over 15 years ago. Is it a coincidence that we both had Samsung drives?
Well all i know today is my old 2011 MBP when i first downloaded and installed the new HS my MBP was almost useless.
After returning to the small menu first used to find the new HS i noticed the software update button, knowing how strange Apple does things there was really little left to try so i clicked on the update to the already up dated HS, you do something and then you do it again.
Well after a long again download and another long install my MBP is working better then when it was new in 2011.
So what do i know today about what Apple had in mind for my MBP as a easy upgrade i have no idea.
After returning to the small menu first used to find the new HS i noticed the software update button, knowing how strange Apple does things there was really little left to try so i clicked on the update to the already up dated HS, you do something and then you do it again.
Well after a long again download and another long install my MBP is working better then when it was new in 2011.
So what do i know today about what Apple had in mind for my MBP as a easy upgrade i have no idea.