New users are not getting verification mail

Hi Richard, 

Welcome to Box Community and glad to assist! 

These are the recommended troubleshooting steps if the user's not receiving email notifications. 

• Check your Spam/Junk email folder. Sometimes, certain email clients do not recognize email from box.com. If you find Box messages in your Spam or Junk folder, add noreply@box.com to your email contacts, or Safe senders list. This will allow most mail clients to recognize Box emails and deliver them to your Inbox.
• Firewall, Content Filter, or Email Security Policy: Check if your firewall or virus scan is blocking the email notifications. Contact your Internet Service Provider (ISP) or Corporate IT department and ask that emails from the following domains be added to the email allow list (safe sender) to ensure that Box messages are not blocked.
  • box.com
  • notify.box.com
  • reply.box.com
  • track.box.com
• Incorrectly typed email address: Is the sender using your correct email address? Just one mistyped letter will cause an email to go to the wrong address or make it undeliverable. Ask them to double-check that they entered your address correctly.
• Email on suppression list: If Box notifications ever bounce, emails are automatically added to our suppression list. Open a case with the support team to check the affected email address(es). 
  
  One avoidable reason for getting on the Box suppression list is from creating a new Box account before your actual mailbox or email account is set up.
• Email scanning issues: If you are experiencing scanning issues, check the HTML code of the templates for any changes and adjust your scripts.

Note: Box "batches" email notifications before sending them out. This means an email may not be sent immediately after an action occurs. When multiple actions are batched/grouped into a single notification, the subject of the email will have the title of the top-level folder. This does not apply to Password Reset emails or Email Confirmation links.

(https://support.box.com/hc/en-us/articles/360043696174-Troubleshooting-Issues-with-Email-Notifications)

Hope it works!