Excel VBA "Method 'Document' of object 'IWebBrowser2' failed"

I ran into this same issue a while back. Use internet explorer at a medium integrity level. InternetExplorer defaults to a low integrity level which, if you are doing this over a local intranet at work, sometimes will give the second error message you show above. Click here for more reading on this. I've modified your code below. Please let me know if that helps.

Sub GoToWebsiteTest()
Dim appIE As InternetExplorerMedium
'Set appIE = Nothing
Dim objElement As Object
Dim objCollection As Object

Set appIE = New InternetExplorerMedium
sURL = "http://example.com"
With appIE
    .Navigate sURL
    .Visible = True
End With

Do While appIE.Busy Or appIE.ReadyState <> 4
    DoEvents
Loop

Set objCollection = appIE.Document.getElementsByTagName("input")

Set appIE = Nothing
End Sub

Remember references for Microsoft Internet Controls, and depending on what you plan on doing further, Microsoft HTML Object Library

Not exactly same as above code but somehow similar , the following code solved my problem:

Do
Loop Until ie.readystate = 3
Do
Loop Until ie.readystate = 4

Just put it before the line you want to start working with the contents. To get more information about how does it work you can check here