New Airport Extreme..Can't access External HD.

I am having a problem with being able to access my External HD. I have a PC and a MacBook. I started out on my PC because it is hardwired into the new Airport Extreme. When I go into the Airport Utility it recognizes my external drive but I can't seem to find where to access it on my machine.

I keep getting the following error when I type in my password to access the disk. "Unknown user, Incorrect password, or login is disabled.Please retype the login information or contact the disk's admin." I know the password is correct because it is the same for being able to join the network.

Can anyone help me?

I finally got an answer to this question and would like to share it for anyone else who has this problem. At this point I'm a little embarrassed due to the ease of solving this problem but here is the answer:

Unplug the USB device from the ABS and then unplug the ABS from the network. Give about 30 seconds and replug the USB device back in to the ABS. Wait 30 more seconds and then reattach the ABS to the network. I did this and it solved my problem on my PC all I had to do was type in the password and everything was a go. I put the install disc that came with the ABS into my MacBook and installed. After install it rebooted and asked for my password. I typed and sure enough there it was. Hope this can help someone else that has the same problem I did.