EventSentry uses the standard Windows ports used for RPC/SMB File sharing to install/deploy, update, and manage the agent. To enable this feature to work with a firewall you should only have to open up the following inbound port on the remote agent:
Port 445, TCP (inbound)
If you are using the Windows Firewall then you may need to allow the default inbound rule called "File and Print Sharing (SMB-IN)".
Alternatively you can also manually install EventSentry on the remote machine without making changes to the firewall configuration.
The easiest option to manually install the agent is to create an MSI file, which is available for EventSentry 3.3 and newer: https://www.eventsentry.com/documentation/help/html/?installationmanualmsi.htm
If you are unable to use an MSI file, you can follow the instructions in KB-352 to manually install the agent by using EXE and dll files.
If you have EventSentry 3.2, please follow KB-297 instead.
If you have EventSentry 3.1 and older, please follow KB-99 instead.