How to remove all the cache in Windows but keep the system?

[tsohk]

Since last month, I have been using a new Macbook pro and I have installed Windows 7 on it via Boot Camp. But until now, I have run the Windows for just once cause I found it useless while the Mac OS X is really sufficient for my daily usage. When I was wondering should I remove the Windows, my friend told me don't cause he said it would be useful when I need it. However I observed that the Windows take up a some of the storage in Mac which is originally 512MB.
So, I want to ask that how to remove all the cache in Windows but keep the system?

 

[macenied]

I guess you mean 512 GB. Short answer is you can not. A usual Bootcamp setup is to store Windows with it's data in one partition. You must delete the partition to be able to use the disk space in OS X again.

 

[ddmcnair]

Download CCleaner, that will help alot. Also in Windows you can uninstall games and other accessories through control panel, programs and features.

Another option is to use a partition utility to split the drive from with the windows. Then get a drive imaging program that runs from within Windows such as Acronis TrueImage and clone the drive. Then you can delete the drive through the Boot Camp assistant.

When you recreate the drive make it slightly bigger than the split disk was and you should be ok when you restore. Make sure you backup the the imaging program installer before you delete the Windows partition from Boot Camp assistant.