If you are not allowed access to the DI-701 management pages, you may be using the wrong password. To regain access, you can reset the router using its console port and HyperTerminal(for Windows).  Reset clears settings to factory defaults, including IP address and login password. Below is the step by step procedure.

Step 1. Power OFF the DI-701

Step 2. Connect a serial cable (RS-232), to the console port on the back of your router.

Step 3. On your computer, go to Start >Program > Accessories > Communications >HyperTerminal.

Step 4. Name the new connection appropriately.

Step 5. In the Connect To dialog box, select the COM port that connects to your DI-701.

Step 6. When the dialog box shown in Figure 10appears, set the Bits per second rate at38400, and Flow control at None. Click OK to complete the setting.

Step 7. Power up the DI-701.

Step 8. You will see text appearing on the screen, it is called the "boot up sequence"

Step 9. Press the key <Esc> then the boot up sequence starts

Then type "-p" and then "-g" to reset the BIOS

You can then reboot the unit and login using the factory default passwords.