Also reduced the code to make it smaller.
Disabled the Buttons after they are picked which was Alex's suggestion.
Added a check for a tie.
Now it asks when the game is over to play again and resets the board or closes the board if no.
code:
Break on
SetConsole("hide")
$root=createobject("Kixgui.Desktop")
If Len($root)=0
Exit 1
EndIf
:Start
$Playagain = "maybe"
$input = "X"
Global $Checkme[8]
$Checkme[0] = "N"
$Checkme[1] = "N"
$Checkme[2] = "N"
$Checkme[3] = "N"
$Checkme[4] = "N"
$Checkme[5] = "N"
$Checkme[6] = "N"
$Checkme[7] = "N"
$Checkme[8] = "N"
; Draws the Starting Board and places it on the Screen
$Board = $root.createform("FrmBoard","Tic Tac Toe Board")
$Board.Width = 310
$Board.Height = 340
$Board.Top = ($Board.parent.height - $Board.height) / 2
$Board.Left = ($root.width - $Board.width ) / 2
; Draws the lines to seperate the board.
$one=$Board.addcmdbutton("cmdStyle1",$1,1,1,98,98,"Choose_click($$one,0,$$input)")
$one.borderstyle=1
$Two=$Board.addcmdbutton("cmdStyle2",$2,1,99,98,100,"Choose_click($$two,1,$$input)")
$Two.borderstyle=1
$Three =$Board.addcmdbutton("cmdStyle3",$3,0,199,99,99,"Choose_click($$Three,2,$$input)")
$Three.borderstyle=1
$Four =$Board.addcmdbutton("cmdStyle4",$4,99,1,100,98,"Choose_click($$four,3,$$input)")
$Four.borderstyle=1
$Five =$Board.addcmdbutton("cmdStyle5",$5,99,99,100,100,"Choose_click($$five,4,$$input)")
$Five.borderstyle=1
$Six =$Board.addcmdbutton("cmdStyle6",$6,99,199,100,99,"Choose_click($$six,5,$$input)")
$Six.borderstyle=1
$Seven =$Board.addcmdbutton("cmdStyle7",$7,199,1,98,98,"Choose_click($$seven,6,$$input)")
$Seven.borderstyle=1
$Eight=$Board.addcmdbutton("cmdStyle8",$8,199,99,99,100,"Choose_click($$eight,7,$$input)")
$Eight.borderstyle=1
$Nine =$Board.addcmdbutton("cmdStyle9",$9,199,199,99,99,"Choose_click($$nine,8,$$input)")
$Nine.borderstyle=1
; Makes the board Visible
$Board.visible = 1
While ($Board.visible) AND ($playagain = "maybe")
$=Execute($Board.lastevent())
Loop
If $playagain = "yes"
Goto start
EndIf
Exit
Function Choose_click($Pick,$num,$Check)
$Pick.fontsize = 75
$pick.enable = 0
$Pick.caption = $input
$Checkme[$num] = $check
$Win = CheckWin($Check)
If ($win = "YES") OR ($Win = "tie")
If $win = "tie"
$Check = "Nobody"
EndIf
$test=MessageBox(" $check won! @crlfDo you want to play again","Tic Tac Toe",4)
If $test = "6"
$playagain = "yes"
Else
$playagain = "no"
EndIf
EndIf
If $Check = "X"
$input = "O"
Else
$Input = "X"
EndIf
Exit
EndFunction
Function Checkwin($input)
Select
Case ($checkme[0] = $input) AND ($Checkme[1] = $input) AND ($checkme[2] = $input)
$checkwin = "YES"
Case ($checkme[3] = $input) AND ($Checkme[4] = $input) AND ($checkme[5] = $input)
$checkwin = "YES"
Case ($checkme[6] = $input) AND ($Checkme[7] = $input) AND ($checkme[8] = $input)
$checkwin = "YES"
Case ($checkme[0] = $input) AND ($Checkme[3] = $input) AND ($checkme[6] = $input)
$checkwin = "YES"
Case ($checkme[1] = $input) AND ($Checkme[4] = $input) AND ($checkme[7] = $input)
$checkwin = "YES"
Case ($checkme[2] = $input) AND ($Checkme[5] = $input) AND ($checkme[8] = $input)
$checkwin = "YES"
Case ($checkme[0] = $input) AND ($Checkme[4] = $input) AND ($checkme[8] = $input)
$checkwin = "YES"
Case ($checkme[2] = $input) AND ($Checkme[4] = $input) AND ($checkme[6] = $input)
$checkwin = "YES"
Case ($checkme[0] <> "N") AND ($checkme[1] <> "N") AND($checkme[2] <> "N") AND($checkme[3] <> "N") AND($checkme[4] <> "N") AND($checkme[5] <> "N") AND($checkme[6] <> "N") AND($checkme[7] <> "N") AND($checkme[8] <> "N")
$Checkwin = "Tie"
Case 1
$Checkwin = "NO"
EndSelect
EndFunction