networking with external hdd

hi guys... since couple of days i m facing a problem that i have external hdd with almost 800gb of data and the external is formatted as FAT32 cuz i m using the same hdd with windows to backup files... i connected this external 1T to my newly bought imac... i have all the pc connected to router...

the problem is that i cannot see this 1T external from my macbook pro... i can login to imac and can see every thing but unable to see this external... i have another external which is formatted as mac and hooked with imac and i can easily connect to it from my macbook pro... i took my 1T external hdd to over my friend's company where they have all mac environment... after connecting to one of the mac and trying to access it from the other mac... same story... it doesn't show...

any solution for this...????

thanx....

nad
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apple imac 20" + macbook pro 15"

You seem to indicate that you were using the drive with a Mac before you purchased the iMac? Is that true or are you just using it to backup files from your PC?

Also...

Are you sure the 1 TB drive is formatted as FAT-32? Using FAT-32 on a drive that size would cause cluster slack that could waste anywhere from 20 to 30 % of the drive's capacity. If the drive is formatted as NTFS that could be the reason the Mac isn't seeing it.

Regards.