If you're using Outlook Express or Windows Mail to send email from QuickBooks, you may see warning messages that another program is trying to send email on your behalf. You can temporarily turn these warnings off.
To do this task
Open Outlook Express or Windows Mail, go to the Tools menu, and click Options.
Click the Security tab and click to clear the Warn me when other applications try to send mail as me checkbox.
To turn these warnings back on, click the checkbox again.
For additional information, click Help in Outlook Express or Windows Mail.