True Image Home Plus 2012 - Daily full backup error - Failed to open data stream.

I do a daily full backup alternating between 2 external drives (one drive backup is on MWFS & the other on TRS). Started getting the error message "Failed to open data stream" with the last line saying "Operation has completed with errors." It started out on just one of the backups now it is both. I have the autoclean-up set, have added only keep 3 old versions (as not to run out of space) but the error continues with every backup. I have attempted to delte the backups, remove them from the list and delete all old backups even reformating the external drives but after a couple of new backups are done, the problem returns. Any thoughts? Error email attached.