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I was trying to change permission on a folder in a Amazon EBS volume mounted on a Amazon EC2 running Ubuntu EC2.

When I entered the command

sudo chmod -R u+rw,go-rw /mnt/my-address

I go the message

sudo: must be setuid root

Now I am unable to SSH into the my Amazon EC2 instance, getting the below message

enter image description here

What is wrong?

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I think your sudo program doesn't have proper permissions.

Change the permissions

chmod 4755 /usr/bin/sudo

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Ok, but how do I access the instance. Unable to SSH only. – Gaurav Agarwal Aug 15 '12 at 17:37
From which machine are you trying to run sudo? – devav2 Aug 15 '12 at 17:44
I am SSHing to Amazon EC2 instance from my Windows 7 machine. – Gaurav Agarwal Aug 15 '12 at 17:45
Not sure about this. @eric-hammond might help you. Please check with him. – devav2 Aug 15 '12 at 17:53

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