You can try this by running regedit:
Find this key: HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer
and this key:
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer
add a dword name: NoLowDiskSpaceChecks
and the value is 1.
Reboot your PC for the change to be effective.
You should not get the message again.
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