Using the "Disk Cleanup" utility on a Windows VPS server requires some attention.
The virtualization software allows you to reduce the space on VPS servers which is dedicated to system files thanks to the use of "symbol links".
Basically, a common space holding numerous system files (which are usually read only files) is created in the physical server, while on the VPS server in actual fact all that is created is a link to the files found in this common space. This allows the user to see these links as if they were actual files and therefore saves a considerable amount of space on the VPS server, space which can then be used for personal data and applications.
The "Disk Cleanup" utility has a function called "Compress old files" which in a normal server or PC allows you to save space by compressing files which are used less frequently.
This utility, however, has an opposite effect on the VPS server, or rather if one of the files found in the common cache of the server is changed on the VPS server, this will cease being merely a link and will become an actual file, taking up real space .
Therefore, the "Compress old files" function must not be used on the VPS server, as it has the opposite effect than the one you intended.
We remind you that the only way to go back to the original situation is to restore a previous backup or, if this is not available, restore the VPS server to the initial conditions.