An odd filesize issue when moving steamapps folder back after steam repair

[anjenthedog]

So...my Steam apps folder had to be moved to repair Steam (broke during an overnight Windows update).

After much backnforth with steam to ensure I didn't f something up, the solution was to

a) move steam apps folder off the harddrive to another drive temporarily.

b) uninstall steam, then reboot

c) reinstall steam and verify it operates 

d) move previously moved steamapps folder back to the proper location in the (new) steam folder

So here's the problem. My system is telling me I don't have enough space on the target drive to perform the move edit: of the temporarily archived /steamapps/... folder back to its original location. This doesn't make sense to me, since there were 80-100 G free on the drive prior to any fiddling, and moving the (149G) folder out should have provided the drive with an additional (149G) of space to work with, so something like 230-250 G all told.

The target is a 500G card from a trad 5G harddrive I use for archiving.

 

Any clues would be helpful.

[7531Leonidas]

Which version of Windows?  I read that there was a bug in the latest W11 update, that set up a region that could not be deleted, resized, or otherwise removed.

[anjenthedog]

Windows 10.

And t'boot, I just archived whatever other files I could off the "root" drive (500G SSD) and got barely enough space to move steamapps and its content back into place, started up Steam, fired up SKSE Loader and...wamp wamp... no go. 

Steam is running now, but instead of the game booting up, I got a new bit of fun

Steam Error
Application load error: 6:0000065432

Like...wtf? SO I searched on that error. saw one (and only one!!!) post that had the same error code and suggested admin status was necessary.

Tried booting steam as admin. nope. Tried SKSE Loader as admin. nope. Tried both as admin. nope.