从vba检查sharepoint上是否存在文件时拒绝访问

我正在尝试从Excel 2010 VBA检查SharePoint 2010中是否存在文件。我从我的电脑上获取了这个代码

当我这样做时，vba抛出一个错误：“此对象的访问被拒绝错误”

它在线路

上失败。发送

我发现错误代码是-2147024891

我检查了Sharepoint权限，应该没有问题。
您需要定义身份验证用户信息

oHttp.SetRequestHeader "Authorization", "Basic " + _
        Base64Encode(authUser + ":" + authPass)

这里有一些信息


我的URL使用http，但对sharepoint的访问权限仅授予https（至少在特定版本）。更改URL解决了访问问题。
我被签入共享空间，所以我想这不会导致问题
Function checkFile( URLStr As String) As Boolean
Dim oHttpRequest As Object
Dim GetResult As  Integer
Set oHttpRequest = New MSXML2.XMLHTTP60
With oHttpRequest
    .Open "GET", URLStr, False
    .setRequestHeader "Cache-Control", "no-cache"
    .setRequestHeader "Pragma", "no-cache"
    .setRequestHeader "If-Modified-Since", "Sat, 1 Jan 2000 00:00:00 GMT"

End With
On Error GoTo HttpError
    oHttpRequest.send '!!!!!!here code stops!!!!!!!
HttpError:
     GetResult    = 00

GetResult = oHttpRequest.Status
If  GetResult  = 200 Then
    checkFile = True
Else
    checkFile = False
End If
End Function

Function checkFile( URLStr As String) As Boolean
Dim oHttpRequest As Object
Dim GetResult As  Integer
Set oHttpRequest = New MSXML2.XMLHTTP60
With oHttpRequest
    .Open "GET", URLStr, False
    .setRequestHeader "Cache-Control", "no-cache"
    .setRequestHeader "Pragma", "no-cache"
    .setRequestHeader "If-Modified-Since", "Sat, 1 Jan 2000 00:00:00 GMT"

End With
On Error GoTo HttpError
    oHttpRequest.send '!!!!!!here code stops!!!!!!!
HttpError:
     GetResult    = 00

GetResult = oHttpRequest.Status
If  GetResult  = 200 Then
    checkFile = True
Else
    checkFile = False
End If
End Function