Hi @ all
I have a HDD which is separated into 2 local disc (C: and D:). Is there any program or method to merge them into one piece ( ex. Local disc C) without formatting the PC?

Thanks beforehand. :)

Is there any program or method to merge them into one piece...

Yes, some repartioning software (such as Acronis Disk Director) will do it. Additional free space is also usually required lack of which can prevent the operation if both partitions are full or close to full. Additionally, doing a full backup beforehand is recommended. But then once a backup it made, I think it is easier to wipe the drive, restore C to a larger partition, and then mount the backup of D and simply copy the contents over to the new larger C. This also sidesteps any free space limitations that might have existed.