Which OSX & Installer to recover my mini I5 2018

[mini5apple]

In reply 18 above, looking at the pics, it looks like the OP has a bootcamp partition on the internal SSD.

I'm thinking that something in this bootcamp partition/setup is causing his problems.

Ultimately, I believe his solution will be:
1. Get an EXTERNAL drive.
2. Clone the contents of his Mac partition (container?) to the backup
3. Test the backup to see if it may be bootable (it MIGHT be, without the bootcamp stuff)
4. If so, now booted from the backup, COMPLETELY ERASE the internal drive to APFS, DESTROYING the bootcamp partition in the process.
5. Now, the OP can attempt to "clone back over" the contents of the backup. It just might work, and he'll again have a bootable Mac partition pretty much "as it was before".

IF that DOESN'T work, the OP could:
a. disconnect the backup
b. NOW try booting to internet recovery
c. Erase the internal drive again, and see what OS the installer offers him
d. Attempt the install now (again, WITHOUT the bootcamp partition), and see if it "goes through". And if it does...
e. Restore data from the cloned backup using setup assistant.

IF internet recovery still won't work, the OP could try booting from a USB flashdrive installer.
If he doesn't have the means with which to create one "at hand", he could go on ebay and buy a USB flashdrive with the installer already on it. Yes, this costs a little $$$. But might solve his problems when the other methods can't.

Finally, if nothing else works, if there's a brick n mortar Apple Store near, the owner could take it to them and ask for a complete erase and OS install. This WILL destroy previous partitions and data on the internal SSD, but if that's what it's going to take to get it bootable again...

OP:
One last bit of advice:
DO NOT attempt to install bootcamp on this one again, eh...?

P.S.
The owner has a 2018 Mini with a t2 chip in it, right?
(I have one of these, also)
I'm wondering if the "startup security" setting could be interfering with things?
(one of the first things I do with an m-series mac is TURN THAT OFF)

I could delete Bootcamp theres nothing Personal on it

Probably going book another appointment at Apple Store Genius surely they can fix it or atlease salvage my Personal data onto a SSD i purchase from them

 

[mini5apple]

OP:

After a thread like this runs on, it gets confusing for an old guy like me as to "where the OP actually is" ...

Does the Mini boot AT ALL?
I don't care what OS is on it.
Can you boot, log in, and get to the finder?

If you can get this far, what OS is currently installed?
(looks like 15.7.1)
Is that correct?

If you can get that far, you should immediately back up your personal data on the internal drive to an external drive.
I'd recommend using SuperDuper (REMARKABLY easy to use) and clone the contents of the internal drive to an external drive (either HDD or SSD). This will create a cloned backup -- it may even be bootable (if the source drive is bootable).

Do you have an external drive onto which you can do this?

With an intel-based Mac, it's not too diffficult to create a bootable clone -- just use SuperDuper or CarbonCopyCloner.

IMPORTANT:
I don't think that either SD or CCC will clone the bootcamp partition (which is probably "the source" of your problems).

Once the clone is done, power down, EVERYTHING off.
Then (make sure the backup is connected and powered on if it has an external power supply) put your finger on the option key and KEEP IT THERE as you press and release the power on button on the Mini. DO NOT LET GO OF OPTION.

Do you see the startup manager?
Is the external drive there?
Now let go of the option key, select the external drive with the pointer, and hit return.

Can you get booted from the external drive?

Thanks I appreciate the help

However i’m not clever enough to do any of that without a step by step walk through

Is this something i could google, does it have a name? Are there YouTube videos?

 

[Fishrrman]

OP wrote:
"However i’m not clever enough to do any of that without a step by step walk through"

Then I'd suggest you either visit the Apple Store or have someone who knows more about Macs and "isn't afraid" help you out...