# Other common problems overview

Source: https://developer.avalara.com/products/ecm/integration-guides/document-management/yhi7523302416054/

Guide: Exemption Certificate Management (ECM)

# Other common problems overview

Learn how to address common authentication problems.

This section explains how to resolve common authentication issues.

Refer to the following topics for detailed solutions:

-   [Routing Problems](/document-management/txx8566418100670/ "Resolve issues with network routing that affect Avalara services.")
-   [Authentication Problems](/document-management/ikt7219668731813/ "Resolve issues with authentication errors or failed API connections.")
-   [Firewall Problems](/document-management/bhl7365110276237/ "Resolve issues connecting to AvaTax caused by firewall restrictions.")
-   [Ethernet Problems](/document-management/css1698126464509/ "Resolve issues with Ethernet performance, such as slow speeds or frequent disconnections.")
-   [Host Files/IP Address Hardcoding/DNS Caching](/document-management/eqa6770822143770/ "Resolve issues with AvaTax connectivity caused by hardcoded IP addresses, host file entries, or DNS caching.")
-   [Proxy Server Problems](/document-management/kma2572942332918/ "Resolve issues with proxy servers causing delays or connection errors when using AvaTax.")
-   [DNS time-to-live](/document-management/zzq9597053810761/)
-   [Need SSL certificate verification](/document-management/ftg8339464344745/ "Resolve SSL certificate verification issues when connecting to Avalara AvaTax.")