I'm not sure of the answer here because I backup my own important files to CD, or to my other PC.
But if your backup program gives you this option it means that you can either backup everything again, and delete and replace your exisitng backup file, or you can just "add" any new files you need to backup to the exisiting backup file.
Can you explain where you backup to?
If you backup to some other destination on your hard disk, you may want to consider an alternative method of backing up.
Backup serves two purposes. It saves your important files if you accidently delete any of them, or it provides you with a complete set of backup files if you lose your hard disk.
The trouble with the latter is that if you have saved the backup file to your hard disk, then if the disk fails at any time, (and hard drives do fail eventually), you many not be able to recover even the backed up data.
It is better, in my view, to backup to a different media, eg CD disks, or to another computer, or both. But to backup to CD, you will need a CDR or CDR/W drive, and the software to copy files to CD using that drive.
Hope this helps.
when I start to back up files, I am given the option to overwrite or append the file. Is one method better than the other, or are they similar enough that it won't matter? Can someone please advise me if one way is better than the other - many of these files are very important business files.