NT scheduler

I developed an VB application which reads an input text file extracts an field then retrieves data from the SQL server database using this feild as key then wirtes the retrieved data to an output text file. I using DAO's for database connection. I created setup for this application using setup wizard of VB. I installed this application on NT server and want to schedule this using winAT scheduler. My problem is when I run the application using command scheduler of NT server the application does not run. But when I run from start menu or run the exe from MS-Dos prompt the application runs without any problems. Since I am passing the database credentials in code there is no question of login problems. Can any one help me ? I will grateful if someone can help me