Web Application Error when installing Action Hub and using Subscription Manager

When installing Action Hub and using Subscription Manager for authentication, you may receive the below “Web Application Error” during the installation process.

Opening up Event Viewer and navigating to the XMPro error log displays the following detailed error message

This error can be caused by Subscription Manager not being able to send out an email notification when it is setting up the Action Hub subscription.

Possible solutions

• Verify that the SMTP configuration entered when installing the Subscription Manager is valid. To update the SMTP configuration settings for the Subscription Manager, see these instructions.
• Verify that Subscription Manager has network access to the configured SMTP server.