In the event that you get a mistake that a message is Undeliverable, this could be because of the sending worker attempting to convey the message yet the activity didn’t finish before the message lapsed. If you are also QuickBooks Unable to Send Emails Due to Network Connection Failure using the QuickBooks Desktop Webmail feature, then the problem is very likely related to the incorrect webmail preferences. Your Email with the attached Invoice should be on its way, and a little pop-up message will confirm that QuickBooks sent it. Before diagnosing the error first, we have to find out why QuickBooks can’t send emails using outlook and why does it freeze. The issues could be the QuickBooks outlook integration or with email settings.
Set up secure webmail
Go to the QuickBooks Edit menu and select Preferences.
Select Send Forms.
Select WebMail and Add.
Select your provider from the drop-down and enter your email address.
Select the Use Enhanced Security checkbox and select OK.
When prompted, sign in to your Intuit account.
Related Post: http://www.reconcilebooks.com/what-is/quickbooks-unable-to-send-emails-due-to-network-connection-failure/
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