OSX First Partition visible and not EFI after Cloning with OSX Installer tool

[Stephan1337]

Hi,

I just tried to move my whole main drive partition (It was just 1 "usable" that I was aware of, with Mac OSX High Sierra) to a new Samsung EVO 850 1TB Harddrive.

I had to initialise it and convert it to "GPT"-format with my Windows 10 Desktop, because the installer tool from High Sierra just could not do that.

So far so good, in the end- it works, the OS boots, everything seems fine.
BUT:
Now I have in the OSX 'harddisk service program' a visible partition in front of my main partition, which seems to be the "System / Guid Table / whatever" Partition for OSX.

When I compare this little partition with the little partition of the old harddisk, which was invisible, the difference is that the old one was "EFI" and this one is not (see screen shots: Disk 4 is the old one, Disk 3 the new one) Also the new one is smaller.

My Questions:

• Firstly, did I do something catastrophical wrong?
• Is it unsafe, or insecure that this partition is visible?
• Will the OS make problems,(absolute file paths e.g.), because "disk0s1" is now not my main OS Partition?
• Will it be problem, that the partition is smaller (128MB vs 200MB) than the old one?

Thank you in advance,
best regards Stephan

 

[Stephan1337]

Solution:

-> Backup everything!
-> Create a boot usb stick from your terminal (google it)
-> Format the HDD and delete all partitions
-> Create EFI Partition with this in terminal:

First check out your partitions:
gpt show -r /dev/disk0

Remove eventually if theres any partition left:
gpt remove -i 1 /dev/disk0
gpt remove -i 2 /dev/disk0
...

Add the EFI System Partition, the GUID tells what it is:
gpt add -i 1 -b 40 -s 409600 -t C12A7328-F81F-11D2-BA4B-00A0C93EC93B /dev/disk0

Afterwards, just install OSX from the USB Stick (or whatever drive) and select the disk as install target.

Voillá!