Save and Restore version 11.0

Help please:smileysurprised

 

I have the above version that seemed to be working fine until a couple of days ago.  I get "Error EC8F17B7 - Target Disk Full"  and a recovery point cannot be set.  I have 2 backups files and alternate between the 2.  Where do I start to correct this?  I have Windows XP, SP2.

 

Thanks for any suggestions. I'm not real "techy", but good at following directions.