If you wish to have all the available disk space in your Windows VPS or Windows server, here are the steps to follow:

First, let's look at the current available space of the C drive:



Now, let's open a command prompt:




Next, run the command diskpart and hit enter:



Then run the command list volume, you should see the current volumes and their size:



now select the volume we want to extend, in this particular case volume 2:




Now extend it by running the command extend filesystem, then hit enter:



That should be it, assuming the volume had available space your C partition should now have all the available space, you can confirm this by going to the Windows explorer:








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