I have a D'Link DIR 615 Router that I have been using for 3 years with Ubuntu 11.10 - with no problems.
I have a Dell Inspiron 15R with dual boot of Windows 7 and now, Ubuntu 12.04 - after a system wipe and re-install of both OS.
I can see all wireless connections active including mine on Windows 7. I can connect with no problems here.
However, on Ubuntu 12.04 I can connect through the router using a wired DHCP connection but when I try to connect via wireless connection, it fails to even find my router and network. It seems to be able to find ALL other active wireless connections in the vicinity.
Please help - I am switching to wired connection whenever I am using Ubuntu :'(