This article describes possible causes and troubleshooting steps for situations where one or more clients cannot register with the TCMS server.

• TCMS registration fails with error "reason: Forbidden"
  • Issue Description
  • Possible Causes and Solutions
    • 1. Restriction due to subnet configuration
    • 2. Faulty TCMS firmware version (13.00 Build 121)

TCMS registration fails with error "reason: Forbidden"

Issue Description

When registering a RangeeOS client with the TCMS, the error message *"reason: Forbidden"* appears:

This message indicates that the client was rejected by the TCMS. In practice, this is typically caused by one of two issues.

Possible Causes and Solutions

1. Restriction due to subnet configuration

In the TCMS Kommbox, under Remote Administration, you will find the option “Allow access from subnets”.  
If one or more subnets are defined here, only clients whose subnet explicitly appears in this list are allowed to register.

Solution:  

• Open the Kommbox of the TCMS.
• Navigate to Remote Administration.
• Add the subnet of the affected clients to the “Allow access from subnets” list, or remove all existing entries.
• Save the settings.
• Restart the TCMS.

2. Faulty TCMS firmware version (13.00 Build 121)

When using firmware 13.00 Build 121, issues may occur if clients attempt to register via the additional API port.  
In this build, access to the API port is incorrectly blocked, causing the *“Forbidden”* message.

Solution:  

• Update the TCMS to a current firmware version in which this problem has been resolved.
• Be sure to follow the official update guide:  
  TCMS – Upgrade or Update the TCMS