Bootcamp Windows 10 El Capitan Trouble

[jrsub]

I have had no luck installing bootcamp Windows 8 or Windows 10 on my late 2015 iMac. The first time I tried with Windows 8 and got Apple support involved resulted in the iMac getting returned. Apple support completely screwed up the main partition and could not return it to its original size.

My second iMac i tried to use bootcamp to install Windows 10. On both machines I got to the same spot where Windows was installing from the ISO file and got to the point where the disk partitions were all listed and I selected the one called bootcamp. When I would select it it would say Windows must be installed to a NTFS partition. When I select format, it would think for a few seconds but then display the partition list with the bootcamp name remove from the partition. When I select "next", it says we could not create a new partition or locate an existing one.

On my first iMac Apple support tried to create and format the bootcamp partition with disk utility since the bootcamp utility wouldn't work. That was not at all successful.

So what's the deal, no bootcamp on El Capitan? Thoughts?

 

[imacken]

I had the exact same issue, and I'm sorry to say, but the only solution was to erase the main partition, reinstall El Capitan and then reinstall Windows via Bootcamp.

 

[Crosscreek]

I have had no luck installing bootcamp Windows 8 or Windows 10 on my late 2015 iMac. The first time I tried with Windows 8 and got Apple support involved resulted in the iMac getting returned. Apple support completely screwed up the main partition and could not return it to its original size.

My second iMac i tried to use bootcamp to install Windows 10. On both machines I got to the same spot where Windows was installing from the ISO file and got to the point where the disk partitions were all listed and I selected the one called bootcamp. When I would select it it would say Windows must be installed to a NTFS partition. When I select format, it would think for a few seconds but then display the partition list with the bootcamp name remove from the partition. When I select "next", it says we could not create a new partition or locate an existing one.

On my first iMac Apple support tried to create and format the bootcamp partition with disk utility since the bootcamp utility wouldn't work. That was not at all successful.

So what's the deal, no bootcamp on El Capitan? Thoughts?

I think I can help you.

1. Go to Bootcamp utilities and use the utility to erase Bootcamp partition so that you have one volume again.
2. Start Bootcamp and go through the procedure of installing the ISO file.
3. Pick Bootcamp partition and format. It will not say Bootcamp when done formatting.
4. when done hit next and when it asks you to use and their are (2 options) pick custom.

That should start the installation process.

 

[jrsub]

I think I can help you.

1. Go to Bootcamp utilities and use the utility to erase Bootcamp partition so that you have one volume again.
2. Start Bootcamp and go through the procedure of installing the ISO file.
3. Pick Bootcamp partition and format. It will not say Bootcamp when done formatting.
4. when done hit next and when it asks you to use and their are (2 options) pick custom.

That should start the installation process.

The problem I have is when I get to your step 4 and hit next. When I do that it says, "we could not create a new partition or locate an existing one".

Just figured it out, after selecting format I was highlighting the partition before hitting next. If I just select next without highlighting the partition formerly named bootcamp it works just fine.

 

[Crosscreek]

The problem I have is when I get to your step 4 and hit next. When I do that it says, "we could not create a new partition or locate an existing one".

Just figured it out, after selecting format I was highlighting the partition before hitting next. If I just select next without highlighting the partition formerly named bootcamp it works just fine.

Glad I could help. Also make sure it installs the Apple tools after Windows is booted and open.

 

[imacken]

The problem I have is when I get to your step 4 and hit next. When I do that it says, "we could not create a new partition or locate an existing one".

Just figured it out, after selecting format I was highlighting the partition before hitting next. If I just select next without highlighting the partition formerly named bootcamp it works just fine.

Glad you sorted it out. I had a really unfortunate experience with installing bootcamp on my new 5k iMac. I have installed Bootcamp many times over the years on many Macs and have never had an issue before my recent experience.
I too had the 'we could not create....' issue, and after trying many things, I gave up as Bootcamp Assistant wouldn't then recognise the partition and the whole process would just stop. Disk Utility wouldn't recognise the partition either so I couldn't delete it or merge it back into the main one.
Under Terminal commands, e.g. diskutil list, the 'partition' would just appear as Free Space.
Various phone calls to Apple Care proved to be fruitless, and in the end they suggested sending the iMac back as 'obviously' the main drive had become corrupted!
Before taking this action, I decided to go into Internet Recovery, reformat the whole fusion drive and reinstall El Cap. Then BCA worked fine and I have had no issues with Windows 10 in Bootcamp or Parallels ever since!