Automatic file(s) deselection from Backup Selection List??

Yesterday I deleted a file called "document.doc" from the C drive but forgot to deselect the file from the backup selection list, so when the backup ran last night the warning below was generated.

Backup- C:
File C:\document.doc is in the backup selection list but was not found.

I went into the selection list this morning and the file was not part of the selection, it has been completely removed from the list. I have manually added this file to the exclusion list so that the warning won't be generated again.

However, my question is as follows: do you always have to manually deselect files from the backup selection list before deleting them from the disk?? Is the backup exec not intelligent enough to recognise a file has been deleted and automatically remove it from the selection list or is this a built in safety/warning feature?? Can backup exec be configured so that if a file is deleted from the disk the backup exec will notice this and automatically deselect the file from the backup list??

Any feedback greatly appreciated.

Thanks in advance!