QBX has a limit to the number of disk files it can have open at any one time, and your program is at that limit. Before this command can be executed, you need to close some of these files. The easiest way to do this is with the BASIC CLOSE statement: 1. Move the cursor to the Immediate window. 2. Enter CLOSE on the first available text line. 3. Press ENTER to execute the statement. You can then execute the QBX command you were attempting before. If your program was running, you will have to restart it.