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WD Elements partition map EFI problem

Hi All,


I am trying to format a 3TB WD Elements (USB 2) external HD, GUID, 1 Partition Mac Extended Journaled. The formatting goes ok.

If I click on the "3TB WD Ext HDD 1021 Media" on the left in Disk Utility and hit "verify disk", I get the following error message:


"the partition map needs to be repaired because there's a problem with the EFI system partition's file system"

A 'repair disk' goes through without hitch, but if I hit 'verify disk' again, I get the same error.


I wonder if I can just disregard this or if I will encounter problems somewhere down the line.



Thank you very much for your help.



(Verify of the actual partition does not yield any problems)

MacBook Pro, Mac OS X (10.7)

Posted on Jul 28, 2011 4:44 PM

Reply
18 replies

Aug 25, 2011 5:20 AM in response to Sonicray

I am having the same problem with the same 3TB WD Elements. Where is the firmware update? When I asked the WD tech about a firmware update he nixed and tried to have me reformat in Apple format!! When I told him it needs to be GUID he switched gears to that. After which the same: "Problems were found with the partition map which might prevent booting. Error: The partition map needs to be re...h the EFI system partition's file system" returning after I removed 3 TB of my life of the drive (hours!) Maybe there are nice people out here that know better than the "Mac" WD technicians. Help please.

W.W.

Nov 30, 2011 3:42 AM in response to Pekeler



I just bought a Seagate 3TB USB Expansion External HD and have exactly the same problem when verifying the disk.


"The partition map needs to be repaired because there’s a problem with the EFI system partition’s file system.”


It repairs ‘ok’ but get the same error message when verifying again.


As this thread has been running for 4 months or so and its still a problem!.... Has anyone had problems using their ‘drives’ while ignoring the error message?


I feel very uneasy trusting the drive as a reliable backup and I'm surprised that Apple hasn't sorted this potentially serious issue out with a 'fix'.... Most especially as it appears to be a fault with 'Lion' rather than the various brands of 3TB external drives?





Jan 6, 2012 11:43 AM in response to phenyl007

I just got this same error message when I was checking my external backup drive which is a G-Drive USB mobile 750GB. I researched the issue on the Web and tried all suggestions. Nothing seems to work. It seems this issue crept up after I updated my OS to the latest version. Does Apple know something and hasn't announced it on the forum board or anywhere else? I am suspicious. I read someone's post on another site that hinted that the problem might be linked to OS. They went on further to say it's likely a deep OS glitch. If anyone has any suggestions for how to eliminate this error I would greatly appreciate the guidance. I am lost for what to do next.

WD Elements partition map EFI problem

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