Hi, Chus,
I will like to clarify a few points about the configuration of your cRIO system. If your cRIO system is offline or disconnected, when you find in it MAX it will show up with a red "x" right next to it. This basically means that the system was previously configured with a specific IP address, but MAX cannot find it there anymore. If you right-click on it and select Change IP (Offline), this just changes the IP where MAX tries to look for the controller: it does not change the IP address that you have configured on your cRIO system.
If the cRIO system is in Safe Mode, you will not be able to find anything under Devices and Interfaces, and it is possible that you will get that VISA error you are mentioning. Basically, when the system boots in Safe Mode, it's just loading a minimum set of drivers (from an onboard non-volatile memory) required for the controller so you can find the controller in MAX, set the IP Address and install software. Software like NI-VISA or NI-RIO is not loaded in memory, that's why you won't be able to target the controller from LabVIEW or open VISA sessions from MAX.
The next step that I would suggest you to do is to reformat the memory on the cRIO by right-clicking on it and selecting Format Disk. After that, your controller will still be in Safe Mode (No Software Installed), but you will be able to install software from MAX.
Please, let me know if you have any problems.
GValdes
National Instruments
