How to stop formatting External HD

After yesterdays problem trying to transfer data from a hard drive to an external hard drive, I found it on ‘computer management’ it said unallocated? I assigned the letter ‘F’,   but every time I click on the external hard drive it wants to format it? I have about 4 years of work stored on it, is there any way to stop the formatting and save my work? Aside pulling the plug? Any help from anyone would be greatly appreciated.

Hello,

You are affecting the drive by letting the format process to begin and then cancelled. As per your description the unit is corrupted, unfortunately you will need a data recovery software or company to recover the data and then reformat the drive to make it operational again.