Are you using the NI 8451?
If so, then you should be using the 845x drivers.If you have a control wired into the device reference in of a 845x VI, then you should have a drop down box with the available 845x resources. When you say greyed out, do you lose the drop down arrow also? Are you able to manually type in the box?
If it is not an 8451, what SPI device are you using? Are you using VISA to interface with this device?
I have been testing this out on my system, and cannot see the behavior you are describing.
Do you have another system to test this on?
Can you try using one of the shipping examples to compare behaviors? (From LabVIEW: Help>>Find Examples...>>Hardware Input and Output>>!2C and SPI>>SPI Basic)
Do you have the latest version of the NI-845x drivers?
Both my VI and my exe are being run on the same machine. For some reason when I create the Executable, the drop down box does not work. The exe is the window on the left side of the screen shot and the vi is the window on the ride side of the screen shot. Its hard to see but on the exe drop down for the device reference, the arrow is grayed and and you cannot select it. The first pictures shows this. Picture number 2 shows the dummy control labeled Visa Resource Name I can select the different ports. and picture 3 shows that I can select the device reference on my vi. It should be noted the control labeled device reference in all of the screen shots was taken right off the NI8451 controls palet in labview while the control labeled VISA Resource Name was taken off the I/O Pallete. I am using the NI USB-8451 USB to I2C device.
Thanks for the screenshots. It looks like there was a similar issue with previous versions of LabVIEW. See this post.
It should be fixed in version 8.5 and later. What version of LabVIEW are you running?