My new core one is having WiFi issues
I have tried to enter my wifi info manually. i have done the wifi wizard and the nfc is also not working im hoping mabe if i connect with ethernet i can do an update and possibly fix it. 
RE: My new core one is having WiFi issues
The error message suggests a hardware problem, and I have not read about any firmware issues which would cause this (and could be remedied by an update). You can check that the Wifi module is properly installed; see the kit assembly instructions for guidance. But you will probably need to contact customer support for further troubleshooting help and possibly a spare part.
You mention that NFC is also not working -- how do you know that? If NFC is indeed not functional, I believe that would point towards a problem on the xBuddy board, because WiFi and NFC share the same chip but use separate antennas and connections. But NFC is temperamental (and of limited use) in the Core One, so the lack of NFC functionality might just be a compatibility or handling problem. You need to know where exactly your phone's NFC antenna is and place that right over the Core One's antenna.
RE: My new core one is having WiFi issues
Oh, one other (and much simpler) option: Several users have reported that they could not connect to WiFi if the SSID or the password contained special characters, including '$ ' or spaces. Not sure what the error messages says in that case, but if your network login info has such special characters, try setting up a network with plain alphanumeric credentials.
RE:
I had the same issue the first time I powered up my kit-built CORE One. I'm not certain of the sequence now, but I think I loaded the latest firmware (COREONE_firmware_6.3.2.bbf) onto the USB before the first power up, and after it flashed the firmware it began the self-tests. It failed at the first step, which is to set up the networking, so I cancelled that and ran through the remainder of the self-tests. At the next power up it then flashed the necessary files onto the wifi module and I was able to get the networking set up properly.
I don't know why it didn't flash the wifi module when I first loaded the firmware - maybe it's an odd combination of updating the firmware while still needing to do the self tests.
RE: My new core one is having WiFi issues
Hi, about the special characters, it is a different issue. The NFC cannot transmit accented characters, it replaces them by '?' and the local keyboard on the printer screen does not provide it neither. The only way I could connect to this WiFi was by scanning networks on which the specials characters are displayed (at least this one), and type the password manually. Hopefully I found each character from the password on the local keyboard.
I don't know if it works from the old config file technique.
https://github.com/prusa3d/Prusa-Firmware-Buddy/issues/4629
Below the example with "WiFi lé la"
So it is a totally different issue here as the printer reports a problem with the wifi module. I would suggest the reseat the module first, maybe reflash the printer firmware then, I am not sure when the printer performs a flash of the wifi module.
RE: My new core one is having WiFi issues
Same message for me at the first start. I pass, make all calibrations, restart the printer and go to the wifi section and it work.
RE:
Same message for me at the first start. I pass, make all calibrations, restart the printer and go to the wifi section and it work.
So it seems possible that the wifi module doesn't get it's firmware flashed until the first run through the self tests. Was yours with the default firmware file on the USB (6.3.1 in my case), or did you also fetch 6.3.2 before first power up?
If indeed it waits for the first self-test before flashing the wifi module, it's odd that it should make connecting to wifi the first thing it attempts.
And I wonder if it needs a successful pass through the self-tests before it allows the wifi module to be flashed.
Or maybe the self-tests have nothing to do with it, and it just needs a reboot after the first firmware flash (which seems more likely).
RE: My new core one is having WiFi issues
Default firmware file on the USB, but mine was 6.3.2
I think that after the firmware was installed, the printer need to be reboot to load the wifi module, but instead of that, the self test start.
RE: My new core one is having WiFi issues
Same message for me at the first start. I pass, make all calibrations, restart the printer and go to the wifi section and it work.
Same for me, i thought it was first worth a try restarting before opening up the back of the printer, thankfully it worked.
RE:
I think that after the firmware was installed, the printer need to be reboot to load the wifi module, but instead of that, the self test start.
Perhaps just an incorrect order of precedence for what needs to be done first when there is more than one outstanding necessary step in the queue - perhaps the need for a self-test overrides the need to reboot. But if this is the case, wouldn't everyone experience the same situation? Or perhaps this new sequence was introduced with 6.3.2?
RE: My new core one is having WiFi issues
Same for me, i thought it was first worth a try restarting before opening up the back of the printer, thankfully it worked.
Ah, 'tech support 101' 🙂
"Have you tried turning it off and on again?"
RE: My new core one is having WiFi issues
Ifti has provided another data point that fits the pattern, i.e. that with 6.3.2 a reboot after completing the self-tests will get the firmware to flash the wifi module. I wonder if it's sufficient to just do a complete run through the self-tests, or whether it actually needs to pass them all.
RE: My new core one is having WiFi issues
So I think I got it to connect to the network because It took my password and now I see the little WiFi symbol in the top corner. But I still can’t connect to PrusaLink or PRUSA app. Support told me my WiFi needs to be a certain frequency or something. Does anyone know how to find out what my WiFi frequency is ?