Windows 8 Upgrade requires 20GB


New Member
I have the developer preview installed and want to upgrade to the consumer preview. Unfortunatly the upgrade is requiring me to have 20GB free. The problem is partition is 35GB's and because it is an upgrade 22GB's is actually in use thanks to the OS. Is there anyway around this?

No I can't just reinstall because I have a MacBook Pro with no optical drive installed, I replaced it with a 2nd HDD after installing the developer preview. And unfortunately it doesn't allow you to boot from a flash drive for the installation.

Any help on bypassing this requirement would be appreciated


U.S.Navy D.A.V.
Hello darknezzx22, welcome.gif to Windows 8 Forums

How do you have your HDD partitions set up? A screenshot of your drive set up would be helpful.

Assuming you have more than one partition, you could shrink down the other partitions as much as possible moving them away from the end of the DP OS, to give you the extra space needed.
A great tool for moving and resizing partitions is EaseUS free Home Edition.

Hope this helps


total T

New Member
i would suggest using partition wizard but the drawback is you would need to boot from the P-wizard boot cd to make it a success.
try resizing your partition as already stated. i had exactly the same issue as you in the size, i had a 30 gb partition and when i tried to upgrade i needed the extra twenty.
fortunately i could format , is it possible for you to get your hands/borrow on a plug in disc drive

Der Stich

New Member
Some good advice here already - but another alternative instead of 'upgrading', delete/format the preview partition and start from scratch.

It needs the extra space while upgrading because it's retaining the original OS install (Windows.old) in case of issues and rollback options.


Extraordinary Member
How about running in Virtual Box. I run it that way and use a total of appr. 13GB (Virtual Box included). Then you can install directly from the .iso.

My Win8 system runs really well. I boot in 8 seconds from Virtual Box and operation is extremely fast. My Win7 host is on a 60GB Crucial M4 SSD but even a normal HDD should work well.

Another option is to mount it in a virtual CD drive (from the .iso). On the 3d page of this tutorial I explain how that is done:!1776&parid=root

If your browser cannot read the PDF directly, you can download it. It is only a 5 page PDF.
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New Member
Thanks! I was able to extend the partition giving me enough room to do the upgrade! Although now I have a completely different problem with IE10 on metro but that's for another thread!


Migrating from the DP to the CP should only be (done) as a clean install not, upgrade.