Question Disk management problem external HD

[WacoJohn]

Got myself in trouble with a dual boot installation of PrimeOS. They have installation instructions whereby one creates their own target partition (blah, blah, blah), but they also have a Windows Installer version. I chose the latter. Well, it blew up with an installation error. I assumed it had not made any changes (In my dreams). From what I can tell though, all I have to do is some allocation of available space and then fix mbr. Therein lies the problem.

Here is what W10-64 Disk Management shows me (screen shot).

https://1drv.ms/u/s!AufnVD2fVv0Yh9pOmKps8xSyW9Wwnw

Need to expand My Book E: partition to use the 31.25 unallocated space ... allowing the entire drive max space (It's a 3TB WD external USB drive). So, I click on the E: partition then click Extend Volume. I get the following:

https://1drv.ms/u/s!AufnVD2fVv0Yh9pPOOVgzDilmdqipw

and I use all default values there. Why? Because I don't really understand what the Wizard is telling me.

Proceeding from there, I get:

https://1drv.ms/u/s!AufnVD2fVv0Yh9pQlSGt9C44PhwWqw

Hmmm, some kind of 2TB limitation. Here is the thing, ... have another W10-64 machine with another IDENTICAL HD which is using the entire drive. 2794.49 GB (PrimeOS never attempted on it).

So I don't know where this limitation is coming from or how to overcome it.

To reiterate ... Before the attempted install of PrimeOS, this HD E: was using all of its capacity just like the other computer is and this limitation is new and unexpected on this problem machine. Both machines are basically identical. Both ext. drives ARE identical.

Sorry for all the links. Can't figure out how to post an inline .png file (screen shot).

 

[R_1]

What's the Difference Between GPT and MBR When Partitioning a Drive?

Need a hundred partitions on a single drive? GPT might be right for you.

www.howtogeek.com

worth the read

quick answer. MBR drive 2TB limit, GPT drives no 2TB limit

 

[WacoJohn]

Thank you for the quick reply. So I assume the botched PrimeOS install converted this disk to MBR(?) I suppose I have to delete all partitions and repartition as GPT and then fix mbr. This computer is not UEFI. The drive must have come NEW GPT because the first time I plugged it in it came up full capacity (I THINK). That was some time ago. Hoping I am on the right track. Thank you again.