Hi David,

Audit for user's last login time and last logout time is added in Forms 10.4.1, you can use following query to check which accounts have logged in Forms within a given period.

SELECT u.username,u.displayname,u.last_login_time,u.last_logout_time
FROM [dbo].[cf_users] AS u
WHERE u.last_login_time is not null AND u.last_login_time BETWEEN '{STARTTIME}' AND '{ENDTIME}'

Is the information enough for your case?