How to meet Windows 8 upgrade's 20 GB requirement on a 40 GB SSD with a 22 GB Windows 7 install?

Solution 1:

NO there is nothing you can do to chop down the size. All that extra space is taken up by DLL backaups and all sorts of things. Windows will decide to delete them in its own time but you cant just go and delete them or windows will fail.

Just do the upgrade and you will be fine. Windows will know what to keep and what to dump. It is likely that it will stay the same size or grow by 5 to 8 gb. If you are just using the SSD for Windows then that will be great. If you are installing applciations and similar then you will run out of space quickly.

TIP

• You have moved the swap file off the SSD correct? It is better to have it on a mechanical drive anyway because it is intense in writes. Here is a video that might help you in Windows 8
• Try and get some more space by using this in elevated terminal dism /online /cleanup-image /spsuperseded /hidesp to remove backup SP files
• You can try and get some more space by removing some windows features - Using control panel and switching to Windows features. Get rid of games, IE8 and some other obvious stuff
• Sometimes uninstalling applications will free up space on on the Windows drive because it can remove some backup DLL's and uninstall images.
• Try using CCleaner to sqish all that hidden cahce files out...
• Use windirstat to see where there are some hidden files that you can delete- sometimes windows caches files in hidden folder that take up ridiculous space....

Result of my biweekly ccleaner run ...

Solution 2:

You can do a clean install of windows 8 on the smaller drive. I did this on a 60GB ssd.

1. Make a windows boot usb. You can do this with a windows tool from in windows, you will need a windows iso, either 7 or 8.
2. If you only had a windows 7 iso, go through the windows 8 upgrade assistant to download windows 8 files, then delete all files from the boot usb and then copy over the windows 8 files in C:\ESD. (That might not be the full path, the end result should be very similar, quite a few files and folders in the root of the usb.)
3. boot from that usb and do a clean install using whole drive.
4. Your license may not work if you accidentally formatted the drive as it will think you didn't upgrade. You can add in a registry key and run a command to fix this. This is easy to find on the web, and is the same method as used for windows 7 upgrade licenses.

Hope it works!