Unable to reboot MacBook Pro after installing new SSD
I have been trying to install a new 240gb Sandisk SSD Plus into my mid 2012 macbook pro but keep having issues on the reboot. I go through the necessary steps of installing the new drive into the computer and copy the files from the old drive when it is externally connected. After, I install the operating system and the computer will restart after install but opens to a blank screen. If i type in the login password while at this blank screen it will bring me to the desktop while running on the new SSD. However, once I try to update the system and has to restart it gets stuck on the loading screen with the spinning wheel below the apple logo.
I have done the recovery startup which allows me to get to the disk utility and have made sure the 1 partition is selected along with the (journaled) operating system then reinstalling the operating system but still has the same issue. I have also tried to use the old hard drive externally connected to reboot but the same wheel appears and wont turn on.
When I originally tried installing the new SSD I first had it externally connected and the old drive internally connected but was unable to make any changes to the disk. If i tried to start up to the externally connected disk it would not recognise it and only would have the old interally connected drive as an option.
I am not sure what else to try so any help would be appreciated!
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Solved the problem. After installing the operating system again I didn't copy any of the files to the new hard drive from the old externally connected drive. This got rid of the rebooting issues completely. Now I will need to copy the applications and files over but not the settings and user from the old drive. Hopefully not transferring these two folders over will avoid having the same reboot issue.
из John Murphy