Earlier I was having some real trouble with my USB.. It seemed to have messed up somehow. This was the output I got when I did ls in terminal. Take a look at this pic showing the output.

http://i47.tinypic.com/mkj10.jpg

After that I tried to format it using gparted, but it wasn't able to unmount. It just kept on looping. So, I decided to go for manual formatting using mkfs. While doing that the command didn't return to prompt after a long time. So, thinking that it hanged I removed the USB in the process and since then I am unable to mount it. This is the output of syslog when I plug in the USB http://paste.ubuntu.com/376872/.

After plugging it in, when I run
Code:

after listing out the hard drive partitions, it doesn't return to the prompt until I either remove the USB or after sometime(may be timeout).

And this is the output of syslog when I remove it, after not getting recognised http://paste.ubuntu.com/376870/

I am not sure what the issue really is but someone suggested that I might be dealing with a broken/corrupted file system. any suggestions to fix things?

The only way that I know of to repair a USB device when the file system is corrupt is to stick it into a Windows machine, go to Start, Run, type cmd for a command line and then type: chkdsk F: /f /r

F refers to the drive letter that is assigned to the USB device which may be different in your case. Don't forget to deactivate it before removal.

If someone knows how to do this in Linux I would like to know.

I have already tried that. But the problem in my case is that the pen drive is no longer recognised so no point of getting mounted. By far I am unable to make it work in windows and linux.