first time root, problem installing su-2.3.6.1+busybox1.19.zip

[ZombieHooker]

I am following this guide

http://forums.androidcentral.com/ve...irst-time-rooting-walk-through-4-28-11-a.html

and am at this section

To establish root you'll need to boot into CWM.

If you are following the guide beginning to end you'll need to reinsert your phones battery.

1. With the phone powered off press and hold the volume up, volume down, and power buttons simultaneously. Hold the buttons until the samsung logo comes up, then goes black, then comes back up. Release the buttons now and you'll enter CWM.
2. Scroll down to "install zip from sdcard" and hit the power button.
3. Scroll down to "choose zip from sdcard" and hit the power button.
4. Scroll down to your "roms" folder, and hit the power button.
5. Scroll down to the su-2.3.6.1+busybox1.19.zip file and hit the power button.


when I hit the power button it asks me to confirm that I want to proceed with the install, I choose the "yes" option, then i receive the following messages

-- Installing: SDCARD:su-2.3.6.1+busybox1.19.zip
Finding update package...
Opening update package...
Installing update...
Deleting files...
Deleting files...
Copying files...
E:Can't symlink /system/xbin/su
E:Failure at line 8:
symlink /system/bin/su SYSTEM:xbin/su
Installation aborted.

What am I doing wrong? What do I need to do to proceed?

please and thank you