Small VB Program To Encrypt, PHP To Decrypt Plain Text File

Encryption: I need a program to be developed in VB. This program will have a simple interface. It will have a button name it "Browse" to browse for a folder. That folder will contained a few plain text files. There should be another button, named it "Submit". When this button is clicked, the program will encrypt each text file in that folder and saved the encrypted file into another folder. The location of this folder should be able to be specified in a configuration file (.conf) file that I can change the folder path later. Please note that this folder path must be able to support network path (\\hostname\folder or \\<ip address>\folder) and map drive (Z:\folder\) I guess there shouldn't be a problem in this. For now, just name the encrypted file name to be the same as the original file name. Decryption: I need a PHP script that will decrypt the encrypted files back to its original and save it into another folder. There will be no interface to this PHP page. On top of the PHP script, there should be a line that specify the folder where the PHP program will grab the encrypted files. The original files will be saved to another folder. Again, there should be a line that specify the location path that I can change later. The encryption that I have in mind to use is Blowfish but please suggest others if you think there are better ones for this purpose. Both the VB program and PHP script ideally should not use external third party plugin. All standard components must be used. Let me know if this is not possible. If it is not possible then whatever components used must be free/open source.