My external hard drive can't be found by my PC...HELP!

hiya i have a 320GB My Passport external hard drivve. i had it partitioned a few months ago but (using the Windows’ Disk Management thingy) i have formatted the entire hard drive; my intention was to format it then do new partitions using the FAT32 format.

but when i reconnected it to my PC and after doing the format my hard drive can’t be found by my PC. it got lost. for some reason even if i refresh it. 

have i done something wrong??? is there a way to remedy this so that i can re-partition and re-format it (to FAT32) again?

Please help!!!

I would follow the directions in the link below for how to format, and try it again.