Trouble Checking for Add-in Update

[JoneKL]

I've written an Add-in in Excel VBA. I'm made a function to check for updates. It uses ie, and looks something like this:

Public Sub UpdateCheck()
    Dim ie As Object
    Set ie = CreateObject("internetexplorer.application")
    ie.Visible = False
    ie.navigate "https://example.com/checkforupdate"

    Do While ie.readystate <> 4: DoEvents: Loop

    Set HTML = ie.document
    If HTML.DocumentElement.innerHTML = "update is available" Then
        MsgBox "An update is ready. Go get it!"
    End If
End Sub

Now I can test that out by running it manually from the Macro dialog. It works great!

My problem is, that I want this sub to run automatically whenever Excel runs. I've tried calling it from "Workbook_Open()" in my add-in, but I found that calling it from there prevents the workbook from opening fully. Excel just displays a grey screen. Not sure what's wrong.

Anyway, when should my update sub get called?

Thanks!

[JoneKL]

Just to be even more clear, if you create and add-in with this code:

Private Sub Workbook_Open()
    Call CheckForUpdate
End Sub

Public Sub CheckForUpdate()
    Dim ie As Object
    Set ie = CreateObject("internetexplorer.application")
    ie.Visible = False
    ie.navigate "https://example.com/checkforupdate"

    Do While ie.readystate <> 4: DoEvents: Loop

    Set HTML = ie.document
    If HTML.DocumentElement.innerHTML = "update is available" Then
        MsgBox "An update is ready. Go get it!"
    Else
        MsgBox "no update"
    End If

    Set ie = Nothing
End Sub

Then save it (as add-in .xlam) and activate it. After that I cannot open any Excel files. I just get the message box and then a grey screen. What's going on?

Also, I'm using Excel 2013 x64.

[AB33]

This line does not appear to me as a correct
If HTML.DocumentElement.innerHTML = "update is available" Then
I suspect the code is freezing because IE is terribly slow and you should use HTTP request instead

[JoneKL]

Thanks. Can you give me an example of using http request?

[AB33]

What do you want to do with code? Here is the bare minimum. It gives you to open and send request. Once you have access, you can play with web page as you do with IE.

Option Explicit

Sub test()
Dim HTMLdoc As Object
          With CreateObject("winhttp.winhttprequest.5.1")
            .Open "GET", "https://www.google.com", False
            .send
            If .statusText <> "OK" Then
            
                MsgBox "ERROR" & .Status & " - " & .statusText, vbExclamation
                Exit Sub
                
            End If
            Set HTMLdoc = CreateObject("HTMLfile")
             HTMLdoc.body.innerHTML = .responseText
            MsgBox HTMLdoc
        End With
End Sub