[SOLVED] "windows.old" 38gb and "windows" 14.8gb. Too much space taken up

On-A-Downer

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Jan 10, 2014
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Hello, I just upgraded to windows 10.

I have a 128gb SSD which I like to keep clean and free of junk.

I also have a 1tb HDD and I put everything on there.

The SSD is only for windows 10 and for whichever game I'm currently playing. When I'm done playing it I will usually uninstall but sometimes I'll move it over to the HDD.

I'm trying to install fallout 4 on the SSD, it's game file size is 38gb and right clicking the SSD tab in windows explorer says I have 40.2gb of free space but halfway through the download it pauses and tells me I don't have enough space. When I check the tab again the free space is reduced to 0 or just a few MB.

Now looking in windirstat I can see that "windows.old" is taking up 38gb of space and "windows" is 14.8gb which seems right.

There's also "pagefile.sys" which has 7.9gb.

Then after that there is "users" 4.8gb.
"ESD" 4gb.

What is "windows.old" and can I delete it ?
Why is SSD space suddenly disappearing mid download of a game ?

Thanks.