Problem uploading file with IE

[ricksimm]

        Dim IE As Object
        Set IE = CreateObject("InternetExplorer.Application")
        IE.Visible = True
        IE.Navigate "http://www.custwebsite.com"
        Do
                If IE.ReadyState = 4 Then
                            IE.Visible = False
                            Exit Do
                    Else
                            DoEvents
                End If
        Loop
        IE.Visible = True
        SendKeys "username", True
        Application.Wait (Now + TimeValue("0:00:02"))
        SendKeys "{TAB}", True
        Application.Wait (Now + TimeValue("0:00:01"))
        SendKeys "password", True
        Application.Wait (Now + TimeValue("0:00:01"))
        SendKeys "{ENTER}", True
        Application.Wait (Now + TimeValue("0:00:04"))
        SendKeys "{TAB}", True
        Application.Wait (Now + TimeValue("0:00:01"))
        SendKeys "{TAB}", True
        Application.Wait (Now + TimeValue("0:00:01"))
        SendKeys "{TAB}", True
        Application.Wait (Now + TimeValue("0:00:01"))
        SendKeys "{TAB}", True
        Application.Wait (Now + TimeValue("0:00:01"))
        SendKeys "{TAB}", True
        Application.Wait (Now + TimeValue("0:00:01"))
        SendKeys "{TAB}", True
        Application.Wait (Now + TimeValue("0:00:01"))
        SendKeys "{TAB}", True
        Application.Wait (Now + TimeValue("0:00:01"))
        SendKeys "{TAB}", True
        Application.Wait (Now + TimeValue("0:00:01"))
        SendKeys "{ENTER}", True                                ' admin functiond
        Application.Wait (Now + TimeValue("0:00:04"))
        SendKeys "{TAB}", True
        Application.Wait (Now + TimeValue("0:00:01"))
        SendKeys "{TAB}", True
        Application.Wait (Now + TimeValue("0:00:01"))
        SendKeys "{TAB}", True
        Application.Wait (Now + TimeValue("0:00:01"))
        SendKeys textfile.txt                                         ' insert upload file name
        Application.Wait (Now + TimeValue("0:00:01"))
        SendKeys "{END}", True
        Application.Wait (Now + TimeValue("0:00:01"))
        SendKeys "{TAB}", True
        Application.Wait (Now + TimeValue("0:00:01"))
        SendKeys "{TAB}", True
        Application.Wait (Now + TimeValue("0:00:01"))
        SendKeys "{ENTER}", True

I use this code to start IE, navigate to a webpage, insert username and password, insert a file name to upload, then TAB to the UPLOAD button and sendkey an ENTER. Most of the waits are so I can watch the process. Everything works fine till I sendkey the ENTER on the UPLOAD button. The first thing that happens is I start getting the slow green progress bars and an eventual failure. Rather than waiting for the failure I use the IE STOP button. Then, if I press enter or click on the UPLOAD button the upload function works perfectly. (using XP and Excel 2007) Any suggestions? Thanks.