I've been having space issues on the Win7 32 bit Computer! Today, I was looking through the Orbiter2010 Addons folder and found a 400 megabyte image file, so I deleted the folder and used the Recycle Bin!
They are tools for compiling Orbiter Add-on's using Microsoft C++! The image file was 400 megabytes! I don't code except for Vinka's, so I deleted the folder!