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What Option I Have To Choose Creating an Install Media/ GUID, Master or Apple?

Hi Gary, I’m using MacOS Catalina version 10.15.4 (19E266).
Now I want to do a clean install, because my system is operatig since 2017 with varios OS updates. Creating an install media isn’t the problem, but there is one point which I have doubts about it!
What schema I have to chose to format the media?

MyVolume-OK
Mac OS Extended (jounaled)-OK

GUID partition table, Master boot record or Apple partition table? That is the question!
Would be nice if you could help me with this issue.
Maybe the words are not perfectly translated, but I run my Mac in german.

Greetings from Spain. Stay at home!!!
—–
Stephan

Comments: 2 Responses to “What Option I Have To Choose Creating an Install Media/ GUID, Master or Apple?”

    4 years ago

    Is there a good reason why you want to do a clean install? It is a long process and there are many pitfalls, so I wouldn't do it unless you have a very good reason. Otherwise you are just taking a risk and wasting your time.

    If you really want to do it, make sure your data is well-backed up, perhaps in 2 or 3 differently places. And prepare to be down for anywhere from a few hours to a day or two as you may forget to restore something or load an app, etc.

    Why build install media at all? Just use recovery mode. There's no reason to build an installer disk unless you are planning to update many machines (like a lab or classroom) and have slow bandwidth.

    I don't think it matters which partition map you use as the instructions at https://support.apple.com/en-us/HT201372 will just set it up for you. But in general, just stick with the basic GUID when formatting.

    Stephan
    4 years ago

    Ok, that was a fast response! Thanks for that.
    My question about partition map is solved, but your answer brings a lot of new ones! Anyway, until my machine don't has a break down, i'll leave it as it is!
    Greetings

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