Software for my business

General information for the business: Business
Kind of development: New program from scratch
Description of requirements/functionality: We urgently require an application which will (on a timer) check a directory and send us a file.

There will needs to be a number of routes coded in, which the user will be able to choose on setup

SFTP
FTP
Both with our without SSH.
VPN

It will also need to cater for proxy's. So in the initial config an option will be needed for the user to enter it

We require that the user does not need to send them manually but automatically sent when the files are placed in a directory. The application will need to be configurable in terms of the actual username setups.

There are a number of third party libraries already out there (http://netftp.codeplex.com/releases/view/95632) which we do not mind you using and adapting for us.

When bidding, please state how you will be programming this, and any libraries you will be using.
Specific technologies required: .net -
OS requirements: Windows
Extra notes: