This is rarely used today so https://www.google.com/search?q=RAS+Async+adapter fills in some blanks. Are you trying to setup dial up Internet?
This is doing my head in at the moment.
Been trying for months to try getting this to work on my HP laptops one has win 7 the other win 8.
RAS Async adapter 2# is not working on my win 8.1 same problem. No-one wants to help with this. Pulling my hair out over it. can anyone tell me how to get it to work? says found software for device but encounted a problem installing it.
the system cannot find the file specified.