I don't have the whole answer, but this question got me thinking.

> If the computer should be shut down by accident or due to power
> failure, I need it to know the date it left off with and "append
file
> " rather than over-write.
>
> This all needs to be done automatically, no user interface.

How about writing the name of the file to the registry when it's
first opened. Then if there's a power outage, when it comes back on,
the program looks for the file named today's date. If it exists, it
will append, if not it will open a new file.

Hope this helps a little.