An AutoHotkey script that restores the use of the scroll wheel on the Microsoft Office Keyboard RT9450, which has not been supported since Windows XP.

KeyWheel.ahk

; Microsoft Office Keyboard RT9450
; written by pondermatic 2015-06-03
; This AutoHotkey 1.1 script makes the scroll wheel work with Windows 7, 8 and 10.
; The wheel has four speeds: slowest, slow, fast, fastest.

; requires AHKHID library from https://github.com/jleb/AHKHID

;  0  1  2  3  4  5  6  7 
; -- -- -- -- -- -- -- -- -----
; 01 01 00 00 00 00 00 00 Help
; 01 00 00 00 01 00 00 00 Office Home
; 01 00 10 00 00 00 00 00 Task Pane
; 01 00 80 00 00 00 00 00 New
; 01 00 00 01 00 00 00 00 Open
; 01 00 00 02 00 00 00 00 Close
; 01 00 00 00 20 00 00 00 Reply
; 01 00 00 00 40 00 00 00 Fwd
; 01 00 00 00 80 00 00 00 Send
; 01 00 20 00 00 00 00 00 Spell
; 01 00 00 04 00 00 00 00 Save
; 01 00 00 08 00 00 00 00 Print
; 01 00 00 10 00 00 00 00 Undo
; 01 00 00 00 10 00 00 00 Redo
; 01 00 00 00 00 01 00 00 =
; 01 00 00 00 00 02 00 00 (
; 01 00 00 00 00 04 00 00 )
;                         Back space
; 
; 01 10 00 00 00 00 00 00 Word
; 01 20 00 00 00 00 00 00 Excel
; 01 00 00 00 02 00 00 00 Web/Home
; 01 40 00 00 00 00 00 00 Mail
; 01 80 00 00 00 00 00 00 Calendar
; 01 00 40 00 00 00 00 00 Files
; 01 00 01 00 00 00 00 00 Calculator
; 01 02 00 00 00 00 00 00 Mute
; 01 04 00 00 00 00 00 00 Volume -
; 01 08 00 00 00 00 00 00 Volume +
; 01 00 02 00 00 00 00 00 Log Off
;                         Sleep
; 
; 01 00 00 00 04 00 00 00 Back
; 01 00 00 00 08 00 00 00 Forward
; 01 00 00 00 00 00 01 00 scroll up slowest
; 01 00 00 00 00 00 21 00 scroll up slow
; 01 00 00 00 00 00 41 00 scroll up fast
; 01 00 00 00 00 00 61 00 scroll up fastest
; 01 00 00 00 00 00 1F 00 scroll down slowest
; 01 00 00 00 00 00 3F 00 scroll down slow
; 01 00 00 00 00 00 5F 00 scroll down fast
; 01 00 00 00 00 00 7F 00 scroll down fastest
; 01 00 00 40 00 00 00 00 Cut
; 01 00 00 20 00 00 00 00 Copy
; 01 00 00 80 00 00 00 00 Paste
; 01 00 08 00 00 00 00 00 Application left (alt-tab)
; 01 00 04 00 00 00 00 00 Application right
; 
;  7 Qualifier Key
; -- -------------
; 00 none
; 01 left control
; 02 left shift
; 04 left alt	
; 08 left windows
; 10 right control
; 20 right shift	
; 40 right alt


#SingleInstance force
#NoEnv  ; Recommended for performance and compatibility with future AutoHotkey releases.
SendMode Input  ; Recommended for new scripts due to its superior speed and reliability.
SetWorkingDir %A_ScriptDir%  ; Ensures a consistent starting directory.

; Set up the AHKHID constants
AHKHID_UseConstants()

; Create GUI to receive messages (won't be displayed)
Gui, +LastFound
hGui := WinExist()

; Intercept WM_INPUT messages
WM_INPUT := 0xFF
OnMessage(WM_INPUT, "InputMsg")

; Register with RIDEV_INPUTSINK (so that data is received even in the background)
result := AHKHID_Register(12, 1, hGui, RIDEV_INPUTSINK)

Return


InputMsg(wParam, lParam)
{
    Local devh, bData, bSize, wheel, direction, speed
    
    Critical
    
    ; Check for the correct HID device
    devh := AHKHID_GetInputInfo(lParam, II_DEVHANDLE)
    vn := AHKHID_GetDevInfo(devh, DI_HID_VERSIONNUMBER, True)
    if (devh == -1)
        or (AHKHID_GetDevInfo(devh, DI_DEVTYPE, True) != RIM_TYPEHID)
        or (AHKHID_GetDevInfo(devh, DI_HID_VENDORID, True) != 1118) ; Microsoft 0x045E
        or (AHKHID_GetDevInfo(devh, DI_HID_PRODUCTID, True) != 72) ; Office keyboard 0x0048
        or (AHKHID_GetDevInfo(devh, DI_HID_VERSIONNUMBER, True) != 292) ; 0x0124
    {
        return
    }
    
    bSize := AHKHID_GetInputData(lParam, bData)
;    hex := Bin2Hex(&bData, bSize)
;    OutputDebug Data: %hex%
;    return
    
    if (bSize != 8) {
        return ; we are expecting exactly 8 bytes
    }
    
    b1 := NumGet(bData, 1, "UChar")
    b2 := NumGet(bData, 2, "UChar")
    b3 := NumGet(bData, 3, "UChar")
    b4 := NumGet(bData, 4, "UChar")
    b5 := NumGet(bData, 5, "UChar")
    
    if (b5 = 0x01) {
        Send {=}
    }
    
    if (b5 = 0x02) {
        Send (
    }
    
    if (b5 = 0x04) {
        Send )
    }
    
    wheelData := NumGet(bData, 6, "UChar")
    if (wheelData) {
        HandleWheel(wheelData)
    }
}

HandleWheel(data) {
    direction := (data & 0x0F) >> 3
    speed := (data>>4) // 2 * 2 + 1
    
    if (direction == 1) {
        Send {WheelDown %speed%}
    } else {
        Send {WheelUp %speed%}
    }
}

; By Laszlo, adapted by TheGood
; http://www.autohotkey.com/forum/viewtopic.php?p=377086#377086
Bin2Hex(addr,len) {
    Static fun, ptr 
    If (fun = "") {
        If A_IsUnicode
            If (A_PtrSize = 8)
                h=4533c94c8bd14585c07e63458bd86690440fb60248ffc2418bc9410fb6c0c0e8043c090fb6c00f97c14180e00f66f7d96683e1076603c8410fb6c06683c1304180f8096641890a418bc90f97c166f7d94983c2046683e1076603c86683c13049ffcb6641894afe75a76645890ac366448909c3
            Else h=558B6C241085ED7E5F568B74240C578B7C24148A078AC8C0E90447BA090000003AD11BD2F7DA66F7DA0FB6C96683E2076603D16683C230668916240FB2093AD01BC9F7D966F7D96683E1070FB6D06603CA6683C13066894E0283C6044D75B433C05F6689065E5DC38B54240833C966890A5DC3
        Else h=558B6C241085ED7E45568B74240C578B7C24148A078AC8C0E9044780F9090F97C2F6DA80E20702D1240F80C2303C090F97C1F6D980E10702C880C1308816884E0183C6024D75CC5FC606005E5DC38B542408C602005DC3
        VarSetCapacity(fun, StrLen(h) // 2)
        Loop % StrLen(h) // 2
            NumPut("0x" . SubStr(h, 2 * A_Index - 1, 2), fun, A_Index - 1, "Char")
        ptr := A_PtrSize ? "Ptr" : "UInt"
        DllCall("VirtualProtect", ptr, &fun, ptr, VarSetCapacity(fun), "UInt", 0x40, "UInt*", 0)
    }
    VarSetCapacity(hex, A_IsUnicode ? 4 * len + 2 : 2 * len + 1)
    DllCall(&fun, ptr, &hex, ptr, addr, "UInt", len, "CDecl")
    VarSetCapacity(hex, -1) ; update StrLen
    Return hex
}

Hi I hope someone can help. I have followed instructions in this thread...
https://www.autohotkey.com/boards/viewtopic.php?p=294145&sid=41e3b706a450a5d3aeafd46da085b03e#p294145

Upon launching KeyWheel.ahk I am getting the following line errors...

Can you please advise what needs to be done in order to get this to work. Many thanks in advance.

You need the item mentioned at the top of the script, that URL is https://github.com/jleb/AHKHID

I placed the files ahkhid.* files in C:\Program Files\AutoHotkey\lib, then was able to run this script, or in my case, simply compiled it into an EXE, so that I no longer need that software installed to utilize it, just moving that EXE over to any computer I need use the full functions of the keyboard on, with of course the MS software for it being installed as well.

Thanks for your reply. I had ahdhid.ahk placed in lib folder, while KeyWheel.ahk was in AutoHotKey directory. Once I have renamed ahdhid.ahk to AHDHID the script started working correctly and scroll wheel is working fine now... Result!

As you mentioned I have tried converting file to EXE however it won't let me save, it was done using autohotkey software Convert .ahk to .exe, might have to look into shell:startup so it will run automatically.

Thanks for your reply. I had ahdhid.ahk placed in lib folder, while KeyWheel.ahk was in AutoHotKey directory. Once I have renamed ahdhid.ahk to AHDHID the script started working correctly and scroll wheel is working fine now... Result!

As you mentioned I have tried converting file to EXE however it won't let me save, it was done using autohotkey software Convert .ahk to .exe, might have to look into shell:startup so it will run automatically.

I can provide you a compiled version if you'd like. I have it placed in my Startup folder in my Start menu, so it always runs.
https://onoitsu2.com/Files/KeyWheel.exe

Thank you very much, you are a star!