This has never been a feature of Windows.
Size isn't an attribute of folders. It's calculated on the fly if you look at its properties. And that takes a rather long time for a large folder. For example, see what happens if you want to know the size of Windows or Program Files folder.
A free program like treesize (from jam-software) shows it, but not in the way you want. See how long it takes for a big disk with 100,000+ files?
Kees
I am currently attempting to have folder sizes shown in lists. I have 'display file size info' checked in Folder Tips check box, to no avail. How can I get Win 7 to display the size of each folder, as it does with file sizes?
Thank you.

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