The SMTP configuration settings in Tableau Server, including server address and port The first step in resolving issues with email delivery from Tableau Server to an external email server is to check the SMTP (Simple Mail Transfer Protocol) configuration settings. This includes verifying the email server address, port, and any authentication details required. Incorrect SMTP settings are a common cause of email delivery issues.
Option A is incorrect because issues with email content and formatting are unlikely to affect email delivery itself. Option C is incorrect as upgrading the email server is not the first step and may not be necessary if the issue is related to SMTP settings. Option D is incorrect because changing the operating system of Tableau Server is an excessive measure and unlikely to resolve an email delivery issue.