But I did install W10 on the 120GB SSD and after the install had 99GB free. This tells me that 120GB isn't the problem here. W10 should be able to install and run fine.
If this is not an install issue but a limitation of partition sizes you'll need to wait for another answer or ask Apple directly.
Hello everyone,
I’ve been trying for a couple of days now (spending hours and hours on it) trying to install Windows 10 Home 64-bit on my Macbook Pro (mid 2012).
I’ve done this (and succeeded) years ago with Windows 7.
In total I have 500GB space and 305GB of it is still free. I’ve got my ISO file, my 64 GB USB and when everything is copied on there through Bootcamp Assistant, it is time to choose the partition size for Windows. I used to have my Windows 7 on 200GB which worked great for me (deleted it for some irrelevant reasons). Now I can only divide about 130GB in total. So MacOS 451GB with 82GB “free” and that makes Windows have 48 GB. The biggest I can make Windows is 120GB. My MacOS is 379GB with 10GB free.
When I started doing this a couple of days ago the numbers were a bit bigger. I could set Windows to 160GB ish (I can’t remember the exact numbers).
I don’t understand this.. I have 300GB FREE. I should be able to put 200GB into Windows and still have 100GB free in MacOS.
I have done a lot of googling trying to find a solution to this, but haven’t found anything. Please, please help me. I would greatly appreciate it!

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