If formatting (takes a long time if you don't do a quick format, but a full format) gives an error also, it's time for a new external HD. If it succeeds there's a good chance that you can copy new files to them and read them also.
But there's every reason to make an extra copy of everything you put on it, because it might become unreliable again.
Hi all,
I'm running Windows 10 and I have a 1TB Seagate Slim external HD formatted as NTFS. Since recently I have been unable to access the drive. Note: I am using an Admin account. I even tried on the built-in Admin account.
First attempt: You do not have permission
Second attempt: I/O error
Then I was searching around and read that my problem could be a permissions thing too, so:
I right click the drive
> Properties
> Security Tab
> (everything is empty because "You must have Read permissions to view the properties of this object"
> Advanced
> All tabs (Permissions/Auditing/Effective Access) are empty because of the "You must have Read permissions" error
> "Owner: Unable to display current owner"
> "Click Continue to attempt the operation with administrative permissions"/"Change" lead to the same error
> "You do not have permission to view or edit this object's permission settings" for both tabs
I also have "Take Ownership" as a line in my context menu which still does not give me permission. Exactly the same errors.
Help anyone?

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