I, too am having a problem connecting an external hard drive that is FAT32. If someone reformatted their external hard drive for Mac and if it worked, please let me know. This has been a problem for me for the last few days and its driving me nuts as well. Thanks to all!
If you reformat that hard drive using Mac OS Journal, you will see the external drive over the network. I had the external drive connected through USB and formatted for Mac OS Journal and could see it from any other computer in the network.