Error: Transfer failed. Reason unknown. TFTP Server Timeout

Overview

This article provides brief information and steps to  resolve the following error while downloading a configuration file:

Transfer failed. Reason unknown. TFTP Server Timeout

Environment

All ETS versions

Resolution

The following are guidelines to resolve the issue:

• Are you using the read-write community string?
  You can verify by entering the IP Address and community string into IP Network Browser. After the device is discovered, right click on the device and select MIBs/System Info... If the tool allows you to change the contact name, then you are using the read-write community string.

• Is there an access list on the router that blocks SNMP queries? 
• Is there a TFTP Server running on your PC?
  You should see an icon with two monitors connected by a red wire running in the system tray.
• Does the Config Viewer have the correct IP address for the TFTP Server?
  If you have the 2002 Edition or the 2001 Edition, then - Select Preferences from the Cisco Config Viewer menu. Select the TFTP Server Address tab and make sure that you have Automatic - Use current IP Address of this computer selected.
• Can you telnet to the router and manually download the configuration?
  If you are unable to manually TFTP the configuration then:

a. Ensure that the TFTP Server has an IP Address that the router can route to. For example, if your network uses     a NAT firewall and the router is on the other side of the NAT firewall, then the IP Address of the TFTP Server     needs to be the external IP Address.
b. Ensure that you can ping the router from the workstation running the TFTP Server. TraceRoute is a good tool to     ensure that there is an open path to the router.
c. Ensure that you can ping the workstation from the router.