Good morning Carla and welcome to the Events Calendar Support forum!
Thank you for reaching out to us.
We are sorry to hear about the 404 error message you are dealing with.
I would love to help you with this topic.
I would recommend trying out the solutions found here: https://theeventscalendar.com/knowledgebase/fixing-http-404-errors/
With that in mind, I am a bit concerned since the latest version of the Events Calendar Pro is actually 4.4.17 . It is very important to have “matching versions” (released at around the same time) for things to go smoothly.
You can always grab the latest copy here: https://theeventscalendar.com/my-account/downloads/
Let me know how that goes.
Best regards,
Geoff B.