回复：什么是‘UPGRADE FIRMWARE’？

Thank you for advice. I have been the website and downloaded the file. However it does not work. Then I went to the vendor. He said I have to reset my adsl modem, which has been connected and used for more than one year. It is a risk for me to do that because I may not be able to return to my current adsl state. Do you think what he said is right?