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Why can't I verify the SMTP Outgoing Email setting for Microsoft Office 365/Outlook?

Article ID: 3028
Last updated: 06 Oct, 2022

If you have any queries setting up the SMTP details in TaxCalc, please contact your IT team in the first instance. You can also review the following:

The information in this article is to provide guidance on what may be required. If you need any further assistance, please contact your IT team, or review the specific provider setting requirements from your email providers website.

When entering your SMTP settings within TaxCalc > Admin Centre, for either your Firm (Office) or a specific User, depending on your email provider settings, the SMTP Email password may require an App Password rather than your email account password.

This is typically if the email provider is using Two Factor Authentication.

To create an app password you will need to review your email account settings.

If you are trying to verify an Microsoft Office 365 email address in TaxCalc, please perform the below steps to enable Authenticated SMTP, before creating an app password:

How to Enable Authenticated SMTP on a Microsoft 365 account:

  • Log in to the Microsoft 365 admin center account as admin from a web browser.
  • Click on the three horizontal lines on the top left of the screen (Navigation menu).
  • Click Users > Active Users > Select the desired user.
  • In the flyout window that appears, click Mail > Manage Email Apps.
  • Check the ‘Authenticated SMTP’ box, then click Save Changes:


  • Close the fly out window, then perform the below steps to create an App Password.

If you are using Microsoft Office 365, you can create an App Password by performing the below steps.

Note: App passwords don't always work immediately, so if it doesn't work straightaway when trying to verify your email address in TaxCalc, please try again shortly afterwards to see if it then works.

If the App Password still does not work after further attempts, please delete the TaxCalc App password and try creating then using a fresh app password to verify your email address in TaxCalc. 

If you don't have administrator rights to the Microsoft Office 365 account, your IT team / Microsoft 365 account administrator will need to perform the below steps:

  • Navigate to and sign in to the desired Microsoft Office 365 account.
  • Under Security Info click Update Info choose your account then click Add a sign-in method > Choose a method > App Password:


  • Click Add:

  • Type TaxCalcPassword or similar, then click Next:

  • Make a note of the password for safe keeping, then click the copy icon to copy the TaxCalcPassword, then click Done:

  • Paste the App Password in to the Email password section of the TaxCalc Add SMTP details page, then click Email passcode:

  • Go to your outlook inbox which will contain an email with the subject TaxCalc SMTP Verification. Open the email and copy the five digit Code and paste it in to the TaxCalc Add SMTP details ‘Verification’ box, then click Verify:

  • You should now see a green tick with ‘Verified’ written next to it, in which case you can then click ‘Save and Close’:

  • Now when you open the TaxCalc Communications Centre module and click Send Message and click the From drop down menu, your email address will appear and you’ll be able to select it:


If you are using a Microsoft Outlook account, you can create an App Password by performing the below steps:

  • Navigate to the Outlook login click sign in and enter your email address then click Next.
  • Enter your Outlook password then click Sign in.
  • Select the desired verification method to log in to the account then proceed to login.
  • Click on your initial on the top right of the screen and click My Microsoft account:

  • Click Security:

  • Click Advanced Security Options:

  • Scroll down to, then click on Create a new app password:

  • Make a note of the app password for safe keeping:

  • Paste the App Password in to the Email password section of the TaxCalc Add SMTP details page, then click Email passcode:

Please note: The location of the app password setting varies per licence type. Therefore, we strongly advise you refer to your email providers support information about Two Factor Authentication and App Passwords.

For more information on app password settings, please refer to your email providers website for support. For example:

For more information on Communications Centre, please see KB3199 Communications Centre: Collateral.

Article ID: 3028
Last updated: 06 Oct, 2022
Revision: 8
Views: 970
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