URGENT HELP PLEASE

Hello folks.I have quite a serious problem which i hope someone can help with.I have an HP Simplesave ext hard drive which has got all of my valuable data on it.Everything from the past 4 years (gulp).I was backing up some videos and some documents from my one to the ext hard drive when the battery ran out before i could get to my power cable.When i plugged the cable in it told me that it had failed to copy some of the data which i thought was ok until i tried to redo it and it came up with an error saying the following $MFTMirr does not match $MFT (record 0). Failed to mount '/dev/sdb1': Input/output error NTFS is either inconsistent, or you have hardware faults, or you have a SoftRAID/FakeRAID hardware. In the first case run chkdsk /f on Windows then reboot into Windows TWICE. The usage of the /f parameter is very important! If you have SoftRAID/FakeRAID then first you must activate it and mount a different device under the /dev/mapper/ directory, (e.g. /dev/mapper/nvidia_eahaabcc1). Please see the 'dmraid' documentation for the details. .
Any ideas folks as i am at a complete loss and in a mild state of panic!!!!
If it is any help then the ext drive works on my friends windows system fine but not on mine.This is VERY URGENT as i live on my own and dont always have access to another system.Thank you in advance.

 

Cancel the last request for help please as i have fixed the problem.I ran a disk check on my friends windows system and it fixed the errors and now i have my beloved research data back.Thank you for your time.

 

Sounds like you should get a second backup - either an external drive or an online storage service - if everything is currently only on the one HP drive.