FTDI not working

Hello, I have an arduino nano 328 and it isn't recognized from windows any more. I used the usbtinyisp to burn again the bootloader and it did not report any errors. But when I connect it with USB windows report "Unknown device". I think it has to do with the FTDI chip. Is there a way to comunicate with the arduino with serial port (TX-RX pins)?
I have the polulu wixel pair in serial connection. Do you think that I could use them to upload a skecth on the nano?
Thank you

I tried it with a "weird" device (USB to serial (5v and 3.3v) http://www.ebay.com/itm/CP2102-USB-TTL-RS232-Serial-Port-Converter-Transceiver-/230308271855 and it works. the only problem is that I have to press reset on the arduino when the IDE is going to upload the binary