time machine stalling

I know this question has been asked before, but none of the other fixes seem to work for me.

Basically my time machine kept freezing at a set data amount, right on 2.83GB of about 500GB of data to back up. I've erased the drive so I currently have NO backups and tried again and it still isn't working. backs up the first bit in about 2 minutes then gets tuck indefinitely ( i left it overnight and still stuck).

running 10.9.5 on iMac 21" i think its a 2011 model? , backup drive is a WD 1TB MyPassport.

Things I have tried:

- erasing the drive

- deleting /Library/Preferences/com.apple.TimeMachine.plist

- restarting my computer

- a combination of all these things

still freezes at the same point, 2.83 GB / 5XXGB

transcirpt from time machine buddy:

Property list invalid for format: 200 (property lists cannot contain NULL)

Starting manual backup

Backing up to /dev/disk2s2: /Volumes/Untitled/Backups.backupdb

Forcing deep traversal on source: "Macintosh HD" (device: /dev/disk0s2 mount: '/' fsUUID: 9F6CE6AC-D834-34ED-B1E8-2BD925281F56 eventDBUUID: 8752988C-ADFB-4C2F-A91F-3CF58C459CB9)

Found 1686645 files (475.39 GB) needing backup

496.87 GB required (including padding), 996.3 GB available

Copied 1529 items (11.6 MB) from volume Macintosh HD. Linked 17642.

Backup canceled.

.... whatever that means.

TY in advance to any body who can sort this....