Troubleshooting CompactRIO connection troubles can be a pain. How do you have it connected to your network?
Normally, I would plug the cRIO onto the same subnet as my laptop and it should find it in MAX. If that doesn't work, try switching the IP Reset switch and rebooting the cRIO so it tries to automatically assign an IP address (and even if that fails - it should find via UDP broadcast) and try to find in MAX again. The key thing is that the cRIO and computer are on the same subnet so the UDP discovery works.
Could also be a firewall issue (e.g. windows firewall).
If you have the cRIO connected directly to your computer, you *might* need to use a crossover cable.
There's also quite a lot of information here and here.
LabVIEW Champion, CLA, CLED, CTD
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