Don't use the built in app. Format it under Windows or boot Parted Magic. I don't think that anyone here can debug Lacie software.
You might look at the partition info under Drive Management and see if you actually have a small partition or you have a messed-up large partition. You may also have to increase the default cluster size to use the whole drive. Per Wikipedia, "...limiting the FAT32 volume size to 2 TB for a sector size of 512 bytes and 16 TB for a sector size of 4,096 bytes."
Like WyomingKnott said the max volume size for a FAT32 is 2 TB, usually you want to format it as a NTFS partition. Also there are many benefits of having a NTFS partition like Compression, Encryption and more.
Cluster size and sector (LBA) size are two different concepts.
Cluster size is a file system concept and is usually expressed as "sectors per cluster".
Sector size refers to the size of the Logical Block, either 512 bytes when accessing the drive directly via SATA, or 4096 bytes when accessing it via the bridge firmware in certain enclosures (eg Seagate 3TB GoFlex or WD 3TB My Book).
You can determine whether the Lacie enclosure is using 4096 or 512-byte LBAs using the following command:
fsutil fsinfo ntfsinfo x: (where x: represents the drive that you are checking)
Almost certainly the issue is that the setup software was instructed to build the disk to be compatible with both Mac and PC and only the FAT32 exchange volume was visible on the PC since Windows won't detect an HFS (OSX) volume.
Deleting the partitions and recreating them in Disk Management is the solution to this. If you intend to only use it on Windows then use NTFS file system.
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