My Book Live 1TB cannot be found by Time Machine

I’ve had a My Book Live 1TB for several months and have a couple of PCs and a couple of Macs backing up to it.  One Mac is still backing up but one stopped backing up a couple of days ago and continues to say it can’t find the drive.   

I tried deleting the old backup using the Dashboard on the My Book Live, and now Time Machine says “The backup disk image “/Volumes/TimeMachine/.sparsebundle” could not be created (error 17).”  

How can I get my Mac Time Machine to work again with this disk?  

I’m connected by WiFi to my router, and the disk is connected to another port on the router. I can see the “MyBookLive” disk in Finder so I don’t think there is a network problem, but the “MyBookLive-backup” shows Connection Failed.  I looked around on the web and some sites talk about using Disk Utility to fix something, but I can’t see the network disk in Disk Utility…  So I’m stuck on how to fix this.  

Any suggestions appreciated.  

Thanks

Mike

Thread moved to My Book Live board.