Hi Roberto,
I saw this message when I first used the PDA emulator but installing VPC resolved it. Are you able to launch the emulator outside of the LabVIEW context? The emulator manager should be at this location: C:\Program Files\Microsoft Device Emulator\1.0\dvcemumanager.exe . You can use the emulator manager to launch specific emulators by right-clicking on them and selecting "Connect".
Also, have you attempted to uninstall and reinstall VPC? You should be able to remove it from the Add/Remove Programs dialog. You can then download a fresh copy
here.
If you are still having problems after trying these things, you may want to check out or post to the
Microsoft Device Emulator Forum. Especially check out
this thread about "Failed to open VPC Network driver".
Hope this helps!
Spex
National Instruments
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