Remove Windows.old From a Server

Delete the windows.old from an upgraded Windows Client:Win7 & above or Server: 2008 & above

For a client OS that's upgraded, the Disk Cleanup utility can be used to delete the very large windows.old folder containing the old OS. This isn't available on a server OS without installing the Desktop Experience feature.

To delete, it is necessary to take ownership of the folder, give administrators full control, then delete. This can be done with the commands below:

• takeown /F c:\Windows.old\* /R /A /D Y
• cacls c:\Windows.old\*.* /T /grant administrators:F
• rmdir /S /Q c:\Windows.old 

Using GUI: I improvised and claimed ownership of the parent folder as well as ensured I had Full Control and that all child folders and files were altered to inherit these attributes - at that point I deleted the folder successfully.