Hi Anja,
The higher level VI's (like easy DIO write.VI, if I remember correctly) will open and close connections to a device. If you would like to do continuous operations to a device with the resets, try one of the lower level VI's or take a closer look at what's happening inside the VI you are working with. (Sorry, No LabVIEW on this machine. Just rebuilt it, you know teenagres...).
What you want to do is open a connection one, do all of your I/O, and only close the connection when you want to exit.
Ben