vb arduino please help

i had been messing around with the code for all day long and finally got one up and running

but still one problem

i transmit SEND in arduino

and receive say SEN one time S onetime SEND one time in vb

(pops up randomly)

the code is

Private Sub Form_Load()
MSComm1.CommPort = 3
' 9600 baud, no parity, 8 data, and 1 stop bit.
MSComm1.Settings = "9600,N,8,1"
' Tell the control to read entire buffer when Input
' is used.
MSComm1.EOFEnable = True

MSComm1.InputLen = 0
MSComm1.RThreshold = 1
' Open the port.
MSComm1.PortOpen = True
End Sub

Private Sub MSComm1_OnComm()
Dim inbuffer() As Byte 'Declare an array of bytes
Dim b() As Byte

Dim i As Long
Dim s As String

Select Case Me.MSComm1.CommEvent
Case comEvReceive
ReDim inbuffer(Me.MSComm1.InBufferCount) 'Specify the size of the array. InBuffercount gives the number of characters in the InputBuffer

inbuffer = Me.MSComm1.Input 'Read the InputBuffer

For i = 1 To 20000
i = i + 1
Next i
 
For i = 0 To UBound(inbuffer) 'Ubound(inbuffer) gives the upper bound of the array, which is equal to the number of characters in the InputBuffer

Me.txtreceive.Text = Me.txtreceive.Text & Chr$(inbuffer(i)) 'TxtReceive is a text box

Next i

s = StrConv(inbuffer, vbUnicode)
End Select

MsgBox s

MSComm1.PortOpen = False

End Sub