Can't save Actiontec configuration file....

I have an Actiontec MI424WR-GEN3I Rev I router and I'd like to save the configuration file as an emergency backup.  I've done this before but now when I navigate to Advanced > Configuration File and click on Save Configuration File I get two pages of alphanumeric characters, bascially jibberish to me, and nothing else happens.

I'm running Win 7 (x64) SP1, Microsoft Security Essentials, and get the same results with IE 11 or Firefox.

Does anyone have a suggestion why this is happening, and/or what I can do to save my configuration file?

Thanks in advance for any ideas.