Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

Macaddict16

macrumors 6502
Original poster
Oct 7, 2002
284
128
I recently had Windows 8.1 on my MacBook Air. When trying to upgrade to Windows 10 I realized I had the 32-bit version of 8.1 installed and I wanted to get it to 64-bit. I have the install media to install 64-bit 8.1 but to do so I had to erase the boot camp partition and start over. This is when I ran into trouble. The previous partition was 30 GB to Windows and the rest to Mac OS X. No for some reason it will not let me select more than 25 GB, which isn't enough to install Windows 8.1 according to the installer. Any ideas? The slider moves, but only between 20 and 25 GB. Really would like to get this installed again, but I can't seem to figure it out.

Thanks so much!

Macaddict16
 

Attachments

  • Screen Shot 2015-08-15 at 11.52.30 PM.png
    Screen Shot 2015-08-15 at 11.52.30 PM.png
    28 KB · Views: 355

Synchro3

macrumors 68000
Jan 12, 2014
1,987
850
If you upgrade from Windows 7 64 Bit to Windows 10 64 Bit, you need around 135 GByte for the system files. Because of the Windows 7 downgrade function, Windows 7 will remain on the SSD after the upgrade.

I recommend an 200 GByte SSD at least. Only for the Windows partition.
 

Macaddict16

macrumors 6502
Original poster
Oct 7, 2002
284
128
I am installing WIndows 8 from scratch. Microsoft says the minimum requirements are 20 GB for the 64 bit version, but it still doesn't let me install it.
 

dusk007

macrumors 68040
Dec 5, 2009
3,415
105
You need to delete the old NTFS partition. Have enough space free on the HFS partition, so you can shrink the HFS partition and create a new NTFS partition.
You don't have to use bootcamp assistent. It is quite limited in its options. Just use disk utility. Just leave enough empty unassigned space at the end of the drive. The windows installer can create the partition with NTFS for itself better than Apple NTFS drivers.

All it currently allows you to do is shrink the NTFS partition by cutting of some free space at the end. You need to make it anew because otherwise you cannot move the starting point of the partition.
 

Macaddict16

macrumors 6502
Original poster
Oct 7, 2002
284
128
You need to delete the old NTFS partition. Have enough space free on the HFS partition, so you can shrink the HFS partition and create a new NTFS partition.
You don't have to use bootcamp assistent. It is quite limited in its options. Just use disk utility. Just leave enough empty unassigned space at the end of the drive. The windows installer can create the partition with NTFS for itself better than Apple NTFS drivers.

All it currently allows you to do is shrink the NTFS partition by cutting of some free space at the end. You need to make it anew because otherwise you cannot move the starting point of the partition.

So when I use disk utility I don't create two partitions? I just remove the space from the current one? Then how do I go about installing Windows and creating the drive for it to be installed on?

Thanks so much!
Macaddict16
 

dusk007

macrumors 68040
Dec 5, 2009
3,415
105
You just shrink the first partition HFS so that their are enough GB left at the end of the drive. You simply delete the NTFS partition.
When you shrink a partition if there is enough free space OSX will move all the files that are in the wrong place and just say the partition ends sooner.

When you start the Windows installer it will ask you on which drive you want to install it. You click the empty space and create an NTFS partition. Then select that partition for installing.
650x492xselect-another-partition-to-install-windows-10-on-in-dual-boot.png.pagespeed.ic.yIBKf7RMjW.png


select empty space
> New partition all the space left
> Fomat partition
> select and click Next
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.