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NETMF-WiFi : unable to connect


I have been trying to make WiFi work in my office environment but having some trouble

MFDeploy log:

Set MAC addr …
mac = 00:1E:C0:02:27:71
Mac address Set
Set regional domain …
region = fcc
Set security …
setting WEP key …
security key set
Scan … for ssid "DCIWIRELESS1 "
[0] bssid = 6C:50:4D:3E:EC:B0
strength = ###…

    indicator = 148

    ssid = DCIWIRELESS1

    channel = 9

AP selected = [0] 

Join …
Authenticate …
Associate …
proceed to disconnect …
Disconnect starting …
Disconnect complete … (1/3)

Following code gives “An unhandled exception of type ‘System.ArgumentOutOfRangeException’ occurred in Microsoft.SPOT.Net.dll” while executing SaveConfiguration function call.

WiFi.Enable(SPI.SPI_module.SPI2, ChipworkX.Pin.PC9, ChipworkX.Pin.PA19);
// WiFi settings
NetworkInterface[] netif = NetworkInterface.GetAllNetworkInterfaces();
Wireless80211 WiFiSettings = null;
for (int index = 0; index < netif.Length; ++index)
if (netif[index] is Wireless80211)
WiFiSettings = (Wireless80211)netif[index];


          WiFiSettings.Ssid = "DCIWIRELESS1";
            //WiFiSettings.PassPhrase = "";                
            WiFiSettings.Authentication = Wireless80211.AuthenticationType.None;
            WiFiSettings.Encryption = Wireless80211.EncryptionType.WEP;
            WiFiSettings.NetworkKey = new byte[] {0x5B, 0xC2, 0x5C, 0x20, 0x0D, 0xD4, 0xE3, 0x6E, 0x8C, 0xB7, 0x22, 0xA4, 0x36 };

            Wireless80211.SaveConfiguration(new Wireless80211[] { WiFiSettings }, false);

Any clues??



You are correct. We found a bug in Wireless80211.SaveConfiguration().
This will be reported to Microsoft NETMF team.

For now to work around this bug add ,0x00,0x00,0x00 to Key array

WiFiSettings.NetworkKey = new byte[] { 0x5B, 0xC2, 0x5C, 0x20, 0x0D, 0xD4, 0xE3, 0x6E, 0x8C, 0xB7, 0x22, 0xA4, 0x36,0x00,0x00,0x00 };


Thanks Joe. Your workaround does allow me to stop the code from throwing exception.
Still I have trouble connecting to WiFi router in our office. It is always failing with message “Associating failed” disconnecting…

I thought of trying something different. I have created Ad-hoc wireless network on my PC and tried to connect from the NetMF-WiFi using MFDeploy as well as from code. MFDeploy log says “No network found…” error.

I was able to connect from my Palm PDA to the same adhoc network fine.

I don’t know what to try next.

By the way I was able to connect NetMF-WiFi at my home using MFDeploy.

Any thoughts and ideas are highly appreciated.


I am pretty sure that the issues are related to router configuration of accepting 2.4GHz/802.11b devices.
I have tried with some other old router in my office, I was able to acquire IP address with NetMF-WiFi.
The new router is Cisco Air - AP1262N-A and the old router is Cisco Air - AP1242A-G.
I will leave the issue to our Network Administrators to figure out the solution.



Ad-hoc is not yet supported.

Do all the routers have the same encryption settings?

Can you try to disable encryption on this specific router and try again?


Yes. All the routers have same encryption. Our admins are replacing old routers with newer ones. So far they have covered one part of the building.

I did indeed tried with one of the new routers with encryption disabled with no apparent luck.

I was under the impression that Ad-hoc is kind of implicit with WiFi. I glad that you have mentioned this otherwise I might be wasting some more time on this.