Int 33 Fn 0020 - Ms Mouse V6.0+ - Enable Mouse Driver [M]
AX = 0020h
Return: AX = status
0020h successful
FFFFh unsuccessful
Notes: restores vectors for INT 10h and INT 71h (8086) or INT 74h (286/386)
which were removed by function 1Fh
Microsoft's documentation states that no value is returned
See Also: AX=001Fh