Please note there is an hourly email limit:
There is no official information posted, however, from our experience, it’s good to send no more than 20 messages an hour from a free Gmail account.  If you are sending more emails than this, you may want to consider setting up an address on a separate domain using G Suite (a business email service from Google) instead.

In Treasury Software:

When setting up Gmail as the email host, after activating the email feature on the first screen, select 'Gmail' on the second screen.

Screen four is for the logo options.

On screen five you will want to create an App Password [see below] for your Gmail account:

Continue through the Email Setup wizard until you can click 'Finish'.

 In Gmail - to create an App Password:

Step 1:

You will want to go to https://security.google.com/settings/security/apppasswords to navigate through the user interface.

Select ‘Mail’ from your ‘Windows Computer’ > then ‘Generate'.  This will create a 16 character unique password.

Step 2:

Paste the password you generated into our software on Screen 5.  Your ‘regular’ Gmail password will not work here.

Shortcut to Creating a Gmail App Password

Go to the following website and login as an admin.
https://myaccount.google.com/

Now search for 'app password'

Next provide a name for the password and click 'Create'.

Lastly, enter this app password into the Treasury Software.