Did you try what Nezovi suggested ? .. Apparently you might have some issues with the paths.
If you try what he suggested and it works at least you have a clue why it does not load the DLLs and you are better prepared to fix it.
It is important the paths and enviroment variables are pointing to the correct places
You can also uninstall java, reboot, and reinstall java (make sure you have the correct java version suggested by the IRI installation guidelines)
When you run your iri node it creates a database and log folder; but if the node never started before there is nothing there.
I use a database folder path in the iota.ini file , like this DB_PATH = db , it creates a folder named db when it starts the first time.
If you do not include a database path the default folder name is mainnetdb
The log file is named mainnet.log
I am not using Windows, but assume it is very similar to what I described.