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My Mac won’t boot up after I have restored it from an old drive to an SSD Firstly we cloned the HDD over to the SSD and tried booting from that and had no luck, this was using carbon copy clone and then afterwards followed a tutorial to delete and restore the drive using Mac’s Disk utility, neither of these will let us boot into the Mac The old drive works and still does, just very slow so wanted to upgrade to an SSD When we load the mac it comes on with a loading bar and the loading bar takes a very long time and eventually gets to the very end but does not go any further.
Yep, makes sense! Cloning apps won’t often restore properly the boot sectors and in your case the OS elements are corrupted so you carried the corruption over to your SSD. Lastly, the hidden partition so the onboard recovery is just not possible as its missing on your cloned drive. Best thing here is to reconnect your old drive externally and then use the Startup Manager to select the external bootable drive (press and hold the Option key) If that’s not possible you’ll need to use Internet recovery pressing the Command (⌘) and R keys. References: Mac startup key combinationsAbout macOS RecoveryHow to reinstall macOS from macOS Recovery But before you do anything more connect another external drive to create a proper Time Machine backup. You’ll needed it at the end! If you have access to another Mac create a bootable OS installer USB thumb drive following this guide: How to create a bootable macOS Sierra installer drive.How to create a bootable macOS High Sierra installer driveHow to create a bootable macOS Mojave installer drive Apple also has a small problem! The OS installer images most people presently have presently or can access has an expired certificate! So they won’t work correctly! Here’s a bit more If you’ve got an old macOS install image, it will probably stop working today Here’s the corrected installers: How to upgrade to macOS SierraHow to upgrade to macOS High SierraHow to upgrade to macOS Mojave OK, so far we’ve gotten the tools we need created and hopefully have a better backup of your current drive. Bootup your system using one of the methods outlined. You’ll want to reformat your SSD using Disk Utility either from the mean in recovery or using the bootable OS installer GUID/HFS+ (Journaled) being the best for SATA SSD drives and only running Sierra. If you have a PCIe/NVMe SSD drive then I would go to Mojave which uses GUID/APFS. The install the macOS onto the drive once done you’ll be given the option to migrate your data from your older system, TimeMachine backup your data. If you jump over this as you want to install the updates first thats fine when you are reasdy open the Utility folder in your Application folder to locate Migration Assistant app. Here’s some deeper details on using it How to transfer your old Mac’s data to your new Mac
