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External hard disk seagate is not readable suddenly and when i click on "Initialize", i am taken to Disk Utility which among other things also says "S.M.A.R.T status" isnt supported. What options do I have now?

I have already verified but i get the error invalid b-tree node size. Thanks .

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I haven't seen an external drive where SMART was supported, so you can probably ignore that aspect and just focus on the rest of the information you can obtain about the drive's health.

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Disk Description : ST932032 5AS Media Total Capacity : 298.1 GB (3,20,07,29,33,376 Bytes) Connection Bus : USB Write Status : Read/Write Connection Type : External S.M.A.R.T. Status : Not Supported USB Serial Number : M6116018VE15 Partition Map Scheme : GUID Partition Table – vats Oct 30 '12 at 16:24 is relevant. When I really need it, I'll pull the drive and connect it directly to SATA. It's generally not a practical thing. – bmike Oct 30 '12 at 16:54
What are the possible reasons for disk utility reading the external HD even though it says unable to read as soon as I connect ? – vats Oct 30 '12 at 18:42

If you have turned on FileVault2 on the external drive, that will disable SMART support and give the "not supported" message.

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