VB App is freezing when displaying Outlook Object - vb.net

Question

I have code that upon click, opens up a pre-defined Outlook Message.
My problem is, when the Outlook message window opens, my VB.Net app freezes until, the Outlook message window is either closed or the mail is sent.
How can I release the object from vb.net so the my app is normal to use and not frozen in time?
My Code:
Dim EmailImgPath, strMsg As String
If CustID = vbEmpty Then
MsgBox("No Client selected. Please select a client first before clicking on the Notifications Email button.", vbExclamation + vbOKOnly, "No Client Selected")
Else
If cmbOrdStatus.Text = "Ready" Then
Try
Dim Outl As Object
Outl = CreateObject("Outlook.Application")
If Outl IsNot Nothing Then
Dim omsg As Object
omsg = Outl.CreateItem(0) '=Outlook.OlItemType.olMailItem'
omsg.To = txtEmail1.Text
omsg.cc = txtEmail2.Text
omsg.bcc = EmailBcc
omsg.subject = "Order Update from EyeStyle Opticians"
strMsg = strMsg & "<p>Dear " & txtFname.Text & ",<br><br>"
strMsg = strMsg & "<p>Great News!"
strMsg = strMsg & "<p>Your order is ready for collection"
strMsg = strMsg & "<p>For any enquiries please call 0734 544376 / 0726 936136 / 0707 908838"
strMsg = strMsg & "<p>Thank you for your patronage and assuring you of our very best services at all times."
strMsg = strMsg & "<p>Karibu."
strMsg = strMsg & "<p>Eyestyle Opticians Ltd.<br><br>"
strMsg = strMsg & "<p><img src=" & EmailImgPath & "></p>"
omsg.HTMLBody = strMsg
omsg.Display(True) 'will display message to user
End If
Outl = Nothing
Catch ex As Exception
MessageBox.Show("ERROR: Failed to send mail: " & ex.Message)
End Try
End If

Answer 1

The following shows how to use Microsoft.Office.Interop.Outlook to send an e-mail. It's been tested.
Pre-requisite: Outlook installed.
Add Reference:
Note: The instructions below are for VS 2019.
In VS menu, click Project
Select Add Reference...
Click COM
Check Microsoft Outlook xx.x Object Library (ex: Microsoft Outlook 16.0 Object Library)
Click OK
Add Imports statement
Imports Outlook = Microsoft.Office.Interop.Outlook
CreateMsg:
Private Sub CreateMsg(toAddress As String)
Dim oApp As Outlook.Application = Nothing
Dim oNS As Outlook.NameSpace = Nothing
Try
'create new instance
oApp = New Outlook.Application()
'get MAPI namepsace
oNS = oApp.GetNamespace("mapi")
'log on using default profile
oNS.Logon()
'logon using specified profile
'oNS.Logon("profileName", System.Reflection.Missing.Value, False, true)
'create MailItem
Dim oMsg As Outlook.MailItem = DirectCast(oApp.CreateItem(Outlook.OlItemType.olMailItem), Outlook.MailItem)
'ToDo: change the message properties as desired (ie: subject, body, etc...)
oMsg.To = toAddress
oMsg.Subject = "this is the subject"
oMsg.Body = "This is a test " & DateTime.Now.ToString("yyyy/MM/dd HH:mm:ss.fff")
'send message
For Each account As Outlook.Account In oApp.Session.Accounts
Debug.WriteLine($"account SMTP address: {account.SmtpAddress}")
If account.SmtpAddress = "desiredFromAddress#outlook.com" OrElse oApp.Session.Accounts.Count = 1 Then
Debug.WriteLine($"Sending from {account.SmtpAddress}...")
oMsg.SendUsingAccount = account
oMsg.Send()
Exit For
End If
Next
'sleep to allow send to complete
System.Threading.Thread.Sleep(150)
'send and receive
oNS.SendAndReceive(False)
'log off
oNS.Logoff()
'oMsg.Display(True)
'oMsg.Display(False)
Finally
If oApp IsNot Nothing Then
oApp.Quit()
End If
End Try
End Sub
Resources:
Microsoft.Office.Interop.Outlook
Work with mail items
How to: Programmatically create an email item
Outlook Automatic Send Receive not Working (Solved)
COM Interop & Outlook - Make Outlook Visible?
How to use the Microsoft Outlook Object Library to retrieve a message from the Inbox by using Visual C#
How to send a mail using Microsoft.Office.Interop.Outlook.MailItem by specifying the From Address
How To: Perform Send/Receive in Outlook programmatically
Outlook error when sending more than one mail: "The item has been moved or deleted"
Outlook Interop: MailItem stuck in Outbox
Outlook Integration in C#