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Macbook pro early 2015 13 inch (16gb ram 256 ssd aftermarket) I am using bigsur in it. Whenever i powers on my machine QUESTION MARK SIGN ON FOLDER starts blinking. Sometimes it appears and sometimes it doesn’t. Totally unpredictable. I have done following things as solutions but sign comes again after somedays. Reset SMC and NVRAM, Disk Utility Repair, Factory reset machine, Reinstalled new OS from bootable drive. Still question mark sign appears after working fine for few days. Really tired and irritated from this issue. Need your help guys, what could be the problem?
The folder with the blinking question mark shows that your MacBook Pro cannot find a boot drive. Since you stated you tried to reinstall MacOS on the internal drive and it didn’t work, I think your SSD may be faulty. For a test, can you install MacOS onto an external drive. To do this, open the “Install Big Sur” app and select the external drive to install to. After MacOS has been installed to the external drive: Shut down the computer.Plug in the external drive.Power on the MacBook Pro, then immediately start holding the option key.Keep holding the option key until the boot picker shows up on the screen.Pick the external drive from the boot picker.Create an account/log in to the MacOS installation.Go to System Preferences>Startup Drive and select the external drive.Reboot the computer a few times to make sure it starts normally. If the computer boots normally with the external drive, it may be time to replace the internal SSD. You can get a new internal SSD here.
I think its time to get a new SSD Sadly, Apples custom interface has a few extra lines to deal with house keeping tasks and TRIM services which these adapter/SSD combo’s are not able to access. So over time they are unable to sustain things. Sorry ;-{ Just to be clear I don’t hate M.2 SSD’s! I have a RAID setup which uses them and I have even a few in external cases. The issue is converting the custom internal Apple interface so a M.2 SSD will work. If Apple had embraced M.2 things would have been so much better. I would go back to the Apple Custom SSD, or either the OWC or Transcend 3rd party SSD’s unlike the M.2 setups these 3rd party SSD’s fully mimic the custom interface and handle the signals fully and correctly.
