Windows 95 can mount, read from, and write to both MS-DOS 6.0 and 6.2 DoubleSpace (MRCI1) and MS-DOS 6.22 DriveSpace (MRCI2) drives in protected mode and real mode. The DriveSpace utility in Windows 95 can mount, unmount, resize, format, delete, change estimated compression ratio, uncompress, show properties of, and so on, for both DoubleSpace and DriveSpace drives.

When the DriveSpace utility creates a new drive (either by compressing an existing drive, or by creating a new, empty compressed drive), it creates it in DoubleSpace format (MRCI1). The reason for this is that during beta testing, Microsoft determined DoubleSpace is more commonly used on systems not running Windows 95. This does not, in any way, suggest you should use DoubleSpace in place of DriveSpace. The code for each has been tuned in Windows 95 to make them substantially faster than the compression in MS-DOS 6.x.