Windows 8 Run Disk Cleanup after 8.1 upgrade

Just to add to Mitchells post.

After installing the 8.1 update via iso I found I had a .windows old folder on the C drive. To remove this run an admin command prompt and type:

cleanmgr/sageset:1

Press enter.

Look for the checkbox marked previous windows installations and check it off. I would advise not checking all the boxes as some files are needed and should only be removed if you know what your doing. Once you've checked off the box click ok and then type:

cleanmgr/sagerun:1

Press enter and Disk clean will cycle.