# ECM FAQs overview

Source: https://developer.avalara.com/products/ecm/integration-guides/document-management/juf6911215351149/

Guide: Exemption Certificate Management (ECM)

# ECM FAQs overview

Find answers to common authentication setup and transaction issues.

This section provides topics for AvaTax authentication. It includes information on credentials, environments, TLS, endpoints, SDK usage, and user management.

Topics covered include:

-   [Can I exempt transactions in Canada?](/document-management/kyo9459003260746/ "Learn how to exempt transactions in Canada using specific exempt reasons and rules.")
-   [How and when does an exemption certificate get applied?](/document-management/bsu3601714101519/ "Learn how to apply exemption certificates in ECM and AvaTax, and when to apply them.")
-   [How do I use a single-use exemption in Exemption Certificate Management (ECM)?](/document-management/mgd7792342619074/ "Learn how to use a single-use exemption in ECM.")
-   [How do I extend my free trial?](/document-management/ehj5302895451328/ "Learn how to extend your AvaTax free trial and explore additional options for Avalara's tax solutions.")
-   [How do I use company profiles?](/document-management/awm5295766065168/ "Learn how company profiles determine tax calculation and manage business-specific details.")
-   [Is SSL required?](/document-management/yej2438976440649/ "Learn if SSL is necessary for using ECM.")
-   [Why is tax being collected for a customer that is set up as exempt in ECM?](/document-management/usm2302988281131/ "Learn why tax might be collected for a customer marked as exempt in ECM.")