Re-use of old HDD as a backup drive

[John Sheppard]

I recently replaced the HDD on my computer with a SSD. I have put the old HDD in an external case for use as a BackUp drive but windows10 still sees multiple partitions on the drive I would like to know how I can wipe the drive completely clean for use as a single 1TB drive. All help appreciated, thanks
John

 

[Hellfire13]

go to disk management and delete the partitions...then format the disk...