I just installed a new SSD
Crucial MX500 to no avail. I am getting the same error message(s): the question mark flashing within a file. This happens with my old hard drive as well as with the new drive. I've tried a variety of different things: Hold the Alt= password and blank screen.
I'm at a loss and am getting ready to throw the thing out

. I've messed up every step of the way and it's far from running smoothly. Sucks to put $ at it and seemingly not know what I am doing

.
Any simple help would be greatly appreciated.
"Simple" is in puter and software terms a difficult wording. And ... yes, there are days where I could throw
it out of the "Windows".
I installed a Samsung Evo SSD which works fine. I can recommend you the following procedure even though I know
it's getting hard to get these "old" OS X installers from Apple in case they might no longer work properly
or might be damaged. But once you have a functional installer file. Keep it as a backup.
- - - > Make a TimeMachine Backup of your current system on an external HDD
1. Go to diskmakerX dot com
2. Download the installer version for the OS X system you want to use
(I tried the DiskmakerX Pro v.1.0 the other day. It failed entirely)
3. Make sure you have the installer OS X file and that it works properly
4. Follow the instruction to create a bootable USB sick with the desired OS X system installer file
5. Restart your puter
6. PRAM reset (alt+cmd+p+r)
7. Insert the USB stick after puter restarted
8. Select the USB drive as your startup disk under System Prefs
9. Restart puter and wait for the OS X bootable USB stick to appear on your screen
10. Launch Disk Utility
11. Format the SSD with Extended journaled (older OS X versions) or APFS (newer OS X versions, High Sierra & higher)
12. Quit Disk Utility
13. Launch the OS X installer on the bootable USB stick
14. Wait for the installation to finish
Done. I know, it's not easy as 1,2,3 ... but at least you have a clean system and a bootable OS X on an external
USB stick which is never bad at all.
When your clean install OS X succeeded. Drag your files manually from a TimeMachine backup drive.
When everything is set up and ready again, create a new fresh and clean backup using TimeMachine.
Regards,
BLACK BARON
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