Hi Suresh,
I've been having some problems with file storage, though the error is file not found so it maybe a different problem.
What version of file storage are you running?
Have you ever upgraded your system or is this same version you have always been running? (I am seeing problems on a site I upgraded but not on a site that has always been 5.0)
Do you have wimpy point installed? (The site I'm having problems on has wimpy point and it seems to be trying to use a wimpy point template)