These are Seagate-owned, design-led products spanning simple portable drives to multi-bay Thunderbolt RAID enclosures. Which you have determines whether this is a straightforward single-drive job or an array reconstruction.
LaCie pairs ordinary Seagate and WD mechanisms with its own bridge, Thunderbolt or RAID boards. When one of those fails, the drive behind it is generally healthy and simply unreachable.
LaCie has been part of Seagate since 2012, and the practical consequence is that most LaCie products contain Seagate mechanisms. The orange bumper, the aluminium body and the Thunderbolt interface are LaCie; the disk inside is usually a Barracuda or a Seagate enterprise drive.
That is worth knowing because it sets expectations. A LaCie Rugged genuinely survives the drops its case was designed for, and beyond that the drive inside fails exactly like any other Seagate. The premium buys physical protection and interface quality, not a different failure profile.
The complication is specific to LaCie: the interface boards. Thunderbolt and USB-C bridges on the higher-end units are more complex than a simple USB adapter, and they fail in ways that make a healthy disk look dead.
Rugged and Rugged Mini 2.5-inch Seagate inside an orange bumper. Survives impact well; the disk fails conventionally.
Rugged SSD and SSD Pro Solid state in the same casing. Controller failure with no warning, as any SSD.
d2 Professional 3.5-inch desktop unit, mains powered. Test the power supply before assuming the drive.
2big and 6big Multi-bay RAID enclosures. Array work rather than single drive — send every member labelled.
Porsche Design Slim aluminium externals. Bridge and connector failure are common relative to disk failure.
Mobile Drive and Fuel Consumer portables. Straightforward construction and conventional failures.
On Thunderbolt and USB-C LaCie units, the bridge is doing considerably more than translating SATA. When it fails, the drive is entirely absent — no sound, no enumeration, nothing — and it is easy to conclude the disk has died when it has not.
Send the whole enclosure including the power supply and the cable. On multi-bay units send every disk labelled by bay. As with any external, do not remove the drive and connect it directly before it has been assessed.
The case is genuinely protective, so a drop it did not survive was probably a serious one. Switch it off and send it; do not power it up repeatedly to check.
Almost certainly, on any LaCie made since 2012. That means Seagate donor matching and Seagate failure patterns apply.
Frequently the power supply on mains-powered models, or the bridge board on bus-powered ones. Both are cheaper outcomes than a failed disk.
Then it is array work from £500 +VAT. Send both disks labelled by bay and do not attempt a rebuild.
From £300 +VAT for single-drive units, £500 +VAT for multi-bay, fixed after the free diagnostic.