I use symbolic links/junctions to deal with the system drive running out of space.
Just as an example:
Say there’s a growing folder in the system drive in C:\Users\MyDirectory\AppData\Roaming\Steinberg
I could copy and paste the directory to some other drive. I.E. G:\Users\MyDirectory\AppData\Roaming\Steinberg (or where-ever you want it). Since all of these are linked to my account I don’t really need to worry about permissions in this case, so next I’d temporarily rename the original directory after copying it.
I.E. Steinberg.bak
Next I’d make a filesystem junction pointing to the new location with the Windows Command Shell:
mklink /J “C:\Users\MyDirectory\AppData\Roaming\Steinberg” "G:\Users\MyDirectory\AppData\Roaming\Steinberg "
Now, as far as software is concerned it’s all on drive C.
Test it out…and once you’re sure it’s working you can go back and delete the directory you renamed “Steinberg.bak”.
You might also find directories growing in places like
C:\ProgramData\Steinberg
C:\Program Files\Common Files\Steinberg
These can also be relocated if needed, but be careful about preserving all the directory and file permissions if you move these about. In these cases, make the changes with a command line in administrative mode, and consider using something like robocopy or xcopy with the proper flags to preserve all the permissions, time stamps, and so forth. The time stamps and all might not be that important, but you do want to be sure the permissions aren’t messed with, as that could lead to apps and plugins not working with all user accounts on the machine.
I’ve a small SSD as a system drive, and I’ve been able to manage system growth for a few years now using such links. To keep me in check about why/when/how I’ve moved things, I drop a readme text in directories that I’ve done this with.