Did you try the method referencing the advanced backup tab. Once you select advanced backup your PC will begin to populate the information that is on you device. Once completed, your data will be displayed on the left side of the screenshot in the Device Database List. If you click once on the first piece of data that is list then hold down your shift key and arrow down. I would suggest selecting 5 pieces of data at a time. Now you can move this data over by selecting the arrows in the center between the two viewing panes. At this point you should have the select data in the viewing panel described as Computer database. Above this panel, select File. You will get a drop down list to choose from. Select open for a previously saved file or select save and your PC should open a window in My Documents. Once you select save your PC will transfer a copy or backup. Once this is done, continue to go down the Device database list and gather the next group of five pieces of data to be saved. Eventually you will find the string of data that is giving you the unknown error. Once you find it, either clear it with the clear tab or just skip over it.