Change file names of new files

I have a program that transfers files to a directory. In this program i am able to run an exe or bat file with arguments against it prior to it writing to the directory. What i'm looking for is a simple program that will run natively on Windows XP that will change the file name based on a predetermined format that will add 1 to each new file based on what was the last number used for renaming. For example: Incoming File is [login to view URL] = Outgoing File is [login to view URL] Incoming File is [login to view URL] = Outgoing File is [login to view URL] Incoming File is [login to view URL] = Outgoing File is [login to view URL] Number should increment to 999 and than reset to 001 and should have the ability to be able to easily reset the number. I will provide a copy of the program we are using for testing purposes. Program should run natively on XP without the use of 3rd party libraries unless justified. Expected completion is within 24 hours of awarded project.