I don't think Cnet builds routers.
Anyway, the best place to ask about these problems is your ISP. He provided the router, and he wrote the instructions.
In fact, even google fails to find hsfinstall.dll. All it has is hsfinstall.wmv and hsfinstall.jpg and those relate to something like cooling a videocard when overclocking it, so it must be something like a hi speed fan. Are you sure you've got the filename correct?
Did you do a search for hsfinst*.* in Windows Explorer already? It would be interesting to see what files your system has. And can you tell your OS, and details about how you installed the router and when the prompt came?
And are you sure Dial-up is the right forum to ask about routers? Mostly, they are associated with broadband (cable/ADSL).
I have just been given a new router by my ISP : it is a 4 Port ADSL2/2+Router built and sold, as I can understand, by CNet. During installation,I was prompted to look for "hsfinstall.dll", which is missing in the provided software documentation. Obviously enough, I tried to find that pieceof software in your websites, and just as unexpectedly, I received the deceiving answer: "Sorry, no match to 4 Port ADSL2/2+Router"!!
Where am I to find it, if CNet websites do not have it ??
I would be very grateful for any help !
Thanks and regards.