I'm trying to do an in-place upgrade from 2008R2 to 2012, everytime I start the process I get a message saying that I don't have enough disk space.

No matter how much space I free up, I keep getting the same message, "not enough disk space on drive C:"

 

Has anyone else seen this message?

When looking for a solution to your scenario, I came across this TechNet article which states that you need to ensure the drive that hosts the Active Directory database (NTDS.DIT) has free space that represents at least 20% of the NTDS.DIT file prior to attempting to upgrade to Windows Server 2012. If there is insufficient disk space, the upgrade can fail as you have experienced several times. As a possible solution, you might want to try an offline defragmentation of the Active Directory as the above article suggests.

 

For more information and resources concerning Windows Server 2012 and Windows 8 you might want to also check out the Windows 8 Springboard Series page on TechNet.

 

Hope this helps!

 

Jessica
Windows Outreach Team – IT Pro