iMac + External HD Mounting Problems...

okay, orginally this was a 250 gb lacie harddrive. however, something happened to it, and the housing needed to be replaced. the lacie never had problems mounting until the housing was changed to some off brand. it connects through usb, and sometimes, it just won't mount. i had tried disk utility and it doesn't even show up on the list. it works fine, or at least, works fine when it actually mounts.

any ideas what's up with my external hd???

^ bump

^ ^ double bump!