No driver for Windows Server 2012 but you can try the one for Windows 8 64bit. Hope it helps.

WA830RE has two operation modes, access point and range extender. You can check its emulator here. http://www.tp-link.com/resources/simulator/TL-WA830RE_V2/Index.htm

After change the Web Management Port, did you reboot the router first before you open port 80 for the server? Can you provide some screenshots to show what you've done on router page?

sb1370 wrote I know it, and I want to buy a wireless router because I think wireless routers provide better results than ADSL wireless modems. I just want to know how is Archer C2 wireless coverage...

How did you access it remotely? You can see Internet Access and public address on USB Settings---FTP Server page, right? In Help, it says "users in a private LAN can access ftp server via Public...

Did you select Get IPv6 prefix delegation? http://forum.tp-link.com/showthread.php?79890-Archer-C9-no-IPV6-Lan-Address&p=156909&viewfull=1#post156909