Adding the line below (in bold) makes this script a little more stable (Thanks Erik!):

' UTLogin.vbs

Set oIE = CreateObject("InternetExplorer.Application")

oIE.Visible = True

oIE.Navigate("www.levelextreme.com")

while oIE.Busy:  wend  ' wait for page to load...

<b>while oIE.Document.ReadyState <> "complete": wend</b>

oIE.Document.All("Key").value="YourUserNameHere"

oIE.Document.All("Password").value="YourPasswordHere"

oIE.Document.Forms(0).Submit