What would make the Salesforce connector become unverified?

The event that would make the Salesforce connector become unverified is the connector user’s Salesforce password was changed. A Salesforce connector is a feature that allows you to connect your Marketing Cloud Account Engagement account with your Salesforce CRM system, and enable bi-directional data sync and alignment between sales and marketing. To verify the Salesforce connector, you need to have a connector user, which is a Salesforce user that Marketing Cloud Account Engagement uses to access your Salesforce data and perform actions on your behalf. The connector user needs to have the appropriate permissions and settings in Salesforce, such as the API Enabled and Modify All Data permissions, and the security token2. If the connector user’s Salesforce password was changed, the security token would also change, and Marketing Cloud Account Engagement would not be able to authenticate with Salesforce. This would cause the Salesforce connector to become unverified, and the data sync between Marketing Cloud Account Engagement and Salesforce would stop. To fix this, you need to update the connector user’s password and security token in Marketing Cloud Account Engagement, and re-verify the Salesforce connector