[ubuntu] Cannot Mount new partition Permission Denied

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http://ubuntuforums.org – Hi, I have a 1TB HDD that I use as my main drive in Ubuntu. I partitioned 250GB of it and left the other 750GB Dormant until I required it, the time has come to partition it and use it to convert all of my kids cartoons from DVD to MP4 for our media player. I created the partition as ext4 and all was good, i even copied data to it. I shut the server down and started it back up as I upgraded the RAM and now when I mount it in Disk Utility I get: An error occurred while performing an operation on "Kids" (Partition 3 of ATA ST31000524AS): Permission Denied Can anybody suggest what (Hardware)