My problem is that whenever I try downloading a big file (100MB or more), it always gets completed but file is corrupted. I have been observing this when downloading Eclipse IDE. I tried many Eclipse versions, Scala IDE, but all result in the same error.

Is there something wrong with my Internet connection or my Hard Drive?

How to diagnose and fix this problem?

*Update *

i tried using another computer to download the same file on the same internet connection. the file download is successful. so it means something wrong in my harddisk only. i checked the Disk 'palimpsest' report and does show many "read errors" and many "Seek Errors" , many "hardware ECC recovered" . But the "Uncorrectable Sector Count" is 0. Does that mean my disk is a problem but it is a recoverable error? what can be done to recover from these errors?

Update 2

i tried attaching my phone as a USB device and downloaded the file in it. the file was downloaded using wget -c command. The same error occured, i.e. extracting the .tar.gz file failed as there was a CRC error
that means Harddisk is OK, and internet connection is OK (see Update 1) , but there is something wrong in the OS? many times i am not even able to apply all updates as the updates also fail for the same reason "Hash Sum Mismatch"
plz help!!