Insufficient Privileges error in Email Notification Links

Our install team receives an automated email notification every time a salesperson enters a new job as sold within Zoho. That team member can then click on the contact name link and review the job details. Recently, one of our install team members has been getting an "insufficient privileges" error when he clicks on the Zoho contact link within the email. He is, however, able to get into Zoho directly and view the contact.

I am the admin and have not made any data sharing changes. Any ideas what would generate this error?

Thanks!