Hiyya yamanash and welcome mate.
I don't know what exactly is going on but you could try the Partition Wizard it may show up what is going on with your drives as in which are partitioned, what is formatted, data on etc
Now did you format the external before yo clone the original drive. I know I always do this with either DISKPART or the Wizard but thats just me being a bit pedantic but at least I am sure that the drive is ready to go and I can get rid of the software hat comes with them as again me I like the drive completely clean of everything.
Partition Manager Server, server partition manager and partition magic server for Windows Server 2000/2003/2008. Server Partition software for Windows Server and None-Server partitions
Disk - Clean and Clean All with Diskpart Command
< be aware that clean all can take some time dependingon disk size