Cisco Router and Security Device Manager (A Few Tips)
By default, Cisco routers must be configured using a Telnet client, either via an IP address or a physical serial cable.
To configure the router with a graphical user interface, you can use the embedded version of Security Device Manager (SDM), which is accessible at http://<ip address>. However, http and https access must be enabled, and a user account created, via the command-line interface (ie. using Telnet). See http://www.cisco.com/en/US/docs/routers/7200/maintain_and_operate/security_device_mgr_guide.7200.7301/sdm7k2_3.html for the steps.
SDM requires Sun Java, but not all versions work properly. Try versions 1.4.2_08, 1.5_09, 1.5.0_06, 1.5.0_07, 1.6.0_02, 1.6.0_03. These are available from the Java Archive Page.
The version of SDM which is embedded in the router is usually an Express version, as there is not enough flash memory for the full version. The full version can be downloaded from cisco.com.
The full version of SDM activates from a launcher, which executes script code from C:. However, various versions of Internet Explorer may not allow this code to run. (You may receive a window call runapp.shtml, showing source code.) To enable this, go to Tools → Internet Options → Advanced Security and tick Allow active content to run in files on My Computer.