When the disk space is low, you can see the hard disk color turn red in Windows File Explorer, as shown below. For example, SharePoint Server Health Analyzer displays a warning when the disk has less than 20% of available space, which means if you have a 1 TB disk the server will give you a low disk space warning when you still have about 200 GB of free disk space on your hard drive. Talking about pagefiles, Windows reserves a certain amount of space on the disk for the pagefile (also known as swapfile), which is used to swap pages in memory to disk if the computer is low on physical memory. Running out of disk space on a Windows computer is fairly common, especially on Windows servers. There are several reasons for low disk space on a computer, such as too much data, too many applications, Windows Updates that have accumulated over the years, you don’t run Disk Cleanup on a regular basis, size and number of the pagefiles, etc.
