I don't think I have used this instrument in the last 10 years or so. I did look at the current driver and I see that it comes with a VI called Fluke 2625A example. Have you tried running this? Instructions are not included in drivers. You are expected to have some familiarity with the instrument by reading it's manual. Have you turned on context help? That should show what each control does and what each function is used for. This is a very old driver and was converted from one that used the old serial port functions. In that old driver, port 0 corresponds to com 1 so that is something to watch out for. The error handling in this is pretty poor as well. You should turn on automatic error dialogs.