External hdd saying needed to be formated

When I try to access my External hardrive which is a 1Tb Iomega 3.5",it comes up with a message from windows saying "You need to format the disk in drive F: before you can use it". I would rather not format it and lose all my stuff on it, so is there anyway of fixing this problem,without formatting it?
would've owned it for about 3months now.It started doing this after i had to restart the computer after it froze,during some copying, and the message occurs only when i try to get access to the external

 

Hello,
Before you try to format it, try recovering your data with Minitools Power Data Recovery (free for home use).

 

Worst case scenario, open up the external enclosure, remove the disk and plug it in internally (assuming you have a desktop) to recover the data. If you are running a laptop then you can buy a USB to SATA converter to use.