How do you know the error occurs in that line?
Because I added code to show which line the error occurs on of course.

Code:
Private Sub tmrCheckPreview_Timer()

Dim lRetVal As Long
Dim lhPrevhWnd As Long
Dim iTmp As Integer
Static iTimesHere As Integer
Static iCurrentIndex As Integer
On Error GoTo ErrHandler
LogIt "tmrCheckPreview Enter"
m_Finished = False
100 If IsWindow(m_PreviewhWnd) And (m_Finished = False) Then
110   iTmp = (iTimesHere \ 10) + 1
120    If iCurrentIndex <> iTmp Then
121        imgTmp.Picture = lblIcon(iTmp).DragIcon
122        picLogo.PaintPicture imgTmp.Picture, 0, 0, picLogo.Width, picLogo.Height
123    End If
124    iCurrentIndex = iTmp
125    iTimesHere = (iTimesHere + 1)
127    If iTimesHere >= 30 Then iTimesHere = 0
Else
130 LogIt "preview unload"
132    tmrCheckPreview.Enabled = False
133    m_Finished = True
134    Unload Me
End If
LogIt "tmrCheckPreview End"
Exit Sub
ErrHandler:
LogIt "tmrCheckPreview Error:" & Err.Description & " Line " & Erl
Resume Next
End Sub
1/21/2013 1:54:47 PM: tmrCheckPreview Error:Client Site not available Line 122