how can i remove background noise

i have a recorded a conversation but there is alot of wind (fan) noice in the background, someone knows how can i remove this noise completely or close.

Removing the noise “completely” is probably not an option.
“Reducing” noise is generally a trade-off between how much noise is removed and how much damage is caused by removing the noise.
See here for some tips about noise reduction: http://wiki.audacityteam.org/wiki/Noise_Removal

Yes, all that. But if it’s simple rumbly, throbbing wind noise, you can do a great deal of good by simply reducing all the frequencies below 100 Hz. We wouldn’t dream of shooting voices outside without the 100 Hz filter engaged in the sound mixer.

Effect > Hi Pass Filter > 100 Hz.

Koz

Shure Brothers makes one packaged for use with your field microphone.

http://www.shure.com/americas/products/accessories/microphones/microphone-problem-solvers/a15hp-inline-high-pass-filter

Koz