Cannot Save myRIO WiFi Settings

Updated Nov 16, 2018

Issue Details

I am trying to change the wireless adapter settings on myRIO in NI MAX but when I click the Save button, a warning prompted as shown below in Figure 1 and it says:
Could not save your changes to the target. One or more settings for wlan0 are invalid.
Details: Cannot change country while wireless interface is in use. Set Wireless Mode to Disabled, change the country, then save.
Figure 1

Solution

This warning usually prompts when you are changing the country setting while the wireless adapter of your myRIO is already in use. 
Just as the warning details suggest, you need to set Wireless Mode to Disabled first and click Save, then you will be able to change and save the country setting.