How to programmatically move Windows taskbar?

I also have this need on Windows 7. Here is my take to do this using autohotkey script:

; This script will try to drag and move the taskbar to where the *current* mouse
; cursor is

; 0x111: WM_COMMAND, 424: lock/unlock taskbar, http://www.codeproject.com/KB/miscctrl/Taskbar_Manipulation.aspx
RegRead, TaskbarLocked, HKEY_CURRENT_USER, SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Advanced, TaskbarSizeMove
If TaskbarLocked = 0
  SendMessage 0x111, 424, , , ahk_class Shell_TrayWnd   

WinActivate ahk_class Shell_TrayWnd
MouseGetPos targetX, targetY
ControlGetPos x, y, w, h, MSTaskListWClass1, ahk_class Shell_TrayWnd
MouseMove x+1, y+1
MouseClickDrag Left, x+1, y+1, targetX, targetY, 10

; often after dragging the taskbar to left or right side of a monitor, even though
; there are enough room to show two columns of icons, it will only show one column,
; it seems showing or hiding an icon will fix this
Menu, Tray, NoIcon
Menu, Tray, Icon

; lock the taskbar if it was previously locked
If TaskbarLocked = 0
  SendMessage 0x111, 424, , , ahk_class Shell_TrayWnd   

I have tested this on Windows 7 with classic window theme. To use this, assign a hotkey to call this script, then position mouse cursor to where you want to drag the taskbar to, then press the hotkey.

I've had some luck with this task in an AutoHotkey script, just in case you don't care about the language used. It uses simulated keystrokes and mouse movements to move your taskbar. I stopped short of automatically unlocking/locking the taskbar.

The hard part was getting it to work reliably. A lot of the code is dedicated to making sure that the taskbar moved. It still doesn't work 100%... it fails like 10% of the time from what I've seen. However, it should be good enough to get you started!

If I ever come back to this script to make it work perfectly, I'll repost here.

Here is the example script (highlighting is a bit odd here, as the language is AHK):

F3::
    reload
return

F5::
    MoveTaskbar(2,"bottom")
return

F6::
    MoveTaskbar(2,"left")
return

F7::
    MoveTaskbar(1,"top")
return

; Move the taskbar
; dspNumber:    number.  device number (primary display is 1, secondary display is 2...)
; edge:         string.  Top, Right, Bottom, or Left
MoveTaskbar(dspNumber, edge)
{
    Critical 
    OutputDebug MoveTaskbar - called to move taskbar to display #%dspNumber% ("%edge%" edge)

    ; absolute coordinate system
    CoordMode, Mouse, Screen

    ; error checking for dspNumber
    SysGet, numMonitors, MonitorCount
    if (numMonitors<dspNumber)
    {
        OutputDebug MoveTaskbar - [ERROR] target monitor does not exist (dspNumber = "%dspNumber%")
        return
    }

    ; get screen position for target monitor
    SysGet, target, Monitor, %dspNumber%

    oX := 7
    oY := 7

    ; get coordinates for where to move the taskbar
    if (edge = "Top")
    {
        oX := (targetRight-targetLeft)/2
        trgX := oX+targetLeft
        trgY := targetTop+15
    }
    else if (edge = "Right")
    {
        oY := -(targetBottom-targetTop)/2
        trgX := targetRight-15
        trgY := -oY + targetTop
    }
    else if (edge = "Bottom")
    {
        oX := -(targetRight-targetLeft)/2
        trgX := -oX+targetLeft
        trgY := targetBottom-15
    }
    else if (edge = "Left")
    {
        oY := (targetBottom-targetTop)/2
        trgX := targetLeft+15
        trgY := oY+targetTop
    }
    else
    {
        OutputDebug MoveTaskbar - [ERROR] target edge was improperly specified (edge = "%edge%")
        return
    }
    trgX := round(trgX)
    trgY := round(trgY)
    oX := round(oX)
    oY := round(oY)

    OutputDebug MoveTaskbar - target location is (%trgX%,%trgY%)
    MouseGetPos, startX, startY
    OutputDebug MoveTaskbar - mouse is currently at (%startX%,%startY%)

    ; request the move mode (via context menu)
    SendInput #b
    SendInput !+{Space}
    SendInput m

    ; wait for the move mode to be ready
    Loop 
    {
        if A_Cursor = SizeAll
            break
    }
    OutputDebug MoveTaskbar - move mode is ready

    ; start the move mode
    SendInput {Right}   

    ; wait for the move mode to become active for mouse control
    Loop 
    {
        if A_Cursor = Arrow
            break
    }
    OutputDebug MoveTaskbar - move mode is active for mouse control

    ; move taskbar (and making sure it actually does move)
    offset := 7
    count := 0
    Loop
    {
        ; move the taskbar to the desired location
        OutputDebug MoveTaskbar - attempting to move mouse to (%trgX%,%trgY%)
        MouseMove, %trgX%, %trgY%, 0
        MouseGetPos, mX, mY, win_id
        WinGetClass, win_class, ahk_id %win_id%

        count += 1

        ; if the mouse didn't get where it was supposed to, try again
        If ((mX != trgX) or (mY != trgY))
        {
            OutputDebug MoveTaskbar - mouse didn't get to its destination (currently at (%mX%,%mY%)).  Trying the move again...
            continue
        }

        ; if the taskbar hasn't followed yet, wiggle the mouse!
        if (win_class != "Shell_TrayWnd")
        {
            OutputDebug MoveTaskbar - window with class "%win_class%" is under the mouse... wiggling the mouse until the taskbar gets over here

            ;offset := - offset
            trgX -= round(oX/2)
            trgY -= round(oY/2)
            oX := -oX
            oY := -oY
            if count = 50
            {
                OutputDebug, MoveTaskbar - wiggling isn't working, so I'm giving up.
                return
            }
        }
        else
            break
    }

    OutputDebug MoveTaskbar - taskbar successfully moved
    SendInput {Enter}
}

The taskbar is a window. Use SetWindowPos() to move it. See also SHAppBarMessage() and ABM_WINDOWPOSCHANGED.

Though the taskbar may be special and Windows may not like you moving it around. There are a lot of special cases in the Shell appbar API implementation for the taskbar.

To move to another monitor, use EnumDisplayMonitors() with GetMonitorInfo(). Some monitors may have negative coordinates.