Winsxs suddenly taking up 80% of disk space

[tuffluck]

Just today I got a notice my SSD was getting too big. Taking a look further, it seems the culprit is winsxs file. I've had this computer for 4 years and have never seen this. It is 35gb in size, that folder alone. What is going on?

 

[Callender]

Take a look here: https://support.microsoft.com/en-gb/kb/2852386

When you install updates, Windows keeps a copy of the original files along with the newer files. Those copies are located in the WinSxS folder.

Note: If you run the Windows Updates cleanup you may not be able to roll back installed updates (if you need to) without reinstalling them first.

 

[tblob]

Also just know that Windows Update cleanup is somewhat broken right now, it is currently removing updates it is not supposed to. So you may have to reinstall a few things after running it.

See here:
FYI: Extended Disc Cleanup has started killing recent Windows Updates
and here
KB3023607 repeatedly removed by deepclean after - Microsoft Community