I am a noob in this stuff, so what I will say will probably make no sense…
Im using an arduino mega connected to an ethernet shield W5100, which is directly connected to the router. I do have an antivirus on the pc but I dont think it is blocking any connections let me try.
By the way the ip, 0.0.0.0, I didnt set that like that, I did try setting other ips but everytime I I upload it always shows up as 0.0.0.0 no matter what
I managed to unblock the port in my router, in putty, now it says connection to host closed. And some 2 green brackets appear in the black window, I could also set the IP for the arduino mega it stopped showing 0.0.0.0 now it actually displays the IP, I could connect it to the site finally after consecutive failures and success in the serial monitor. Thanks for the putty advice!
For anyone that has this same problem with arduino mega, check that if the ICSP pins are correctly connected and if the pins you are using are connected to the 50,51,52 and 10 or 53 for ethernet and 4 for sd card.
HI,
I have the same problems . Connect Mega 2560 over Wifishield upload sketch and got the message wifi connected Ip… and then
[519625] Connecting to arduino.mydevices.com:8442
[530627] Connecting to arduino.mydevices.com:8442
[540631] Connecting to arduino.mydevices.com:8442
[550634] Connecting to arduino.mydevices.com:8442
[560637] Connecting to arduino.mydevices.com:8442
[570640] Connecting to arduino.mydevices.com:8442
[580642] Connecting to arduino.mydevices.com:8442
and on dashboard : waiting for board to connect
With putty I got the message : Connection closed by remote host’
Tried many times to connect , upload sketch again and tried to open ports but every time the same.
Can you try editing CayenneDefines.h and use the ip address instead, 54.86.250.218.
Some Arduinos don’t handle DHCP so well.
Cheers,
Craig
I tried to edit CayenneDefines.h with texteditor and change arduino.mydevices.com to 54.86.250.218 . But the same problem. Should I include CayenneDefines.h into the sketch?
The message should now be:
Connecting to 54.86.250.218:8442.
Please confirm.
Yes message is Connecting to 54.86.250.218:8442. But in a loop and the dashboard is loading
So if it continues to say connecting, you can change it back, it’s not a dhcp issue.
What wifi shield model are you using?
Can you share your sketch so someone else can verify?
Cheers,
Craig
Ok thank you. I use the normal wifi shield from arduino .
I change only Wifi account and token in the sketch
/*
Cayenne WiFi Example
This sketch connects to the Cayenne server using an Arduino WiFi shield
and runs the main communication loop.
The Cayenne Library is required to run this sketch. If you have not already done so you can install it from the Arduino IDE Library Manager.
Steps:
For Cayenne Dashboard widgets using digital or analog pins this sketch will automatically
send data on those pins to the Cayenne server. If the widgets use Virtual Pins, data
should be sent to those pins using virtualWrites. Examples for sending and receiving
Virtual Pin data are under the Basics folder.
*/
//#define CAYENNE_DEBUG // Uncomment to show debug messages
#define CAYENNE_PRINT Serial // Comment this out to disable prints and save space
#include <CayenneWiFi.h>
// Cayenne authentication token. This should be obtained from the Cayenne Dashboard.
char token = “Token”;
// Your network name and password.
char ssid = “NetworkSSID”;
char password = “NetworkPassword”;
void setup()
{
Serial.begin(9600);
Cayenne.begin(token, ssid, password);
}
void loop()
{
Cayenne.run();
}
As written, that sketch will not compile. Try this:
/*
Cayenne WiFi Example
This sketch connects to the Cayenne server using an Arduino WiFi shield
and runs the main communication loop.
The Cayenne Library is required to run this sketch. If you have not already done so you can install it from the Arduino IDE Library Manager.
Steps:
1. Set the token variable to match the Arduino token from the Dashboard.
2. Set the network name and password.
3. Compile and upload this sketch.
For Cayenne Dashboard widgets using digital or analog pins this sketch will automatically
send data on those pins to the Cayenne server. If the widgets use Virtual Pins, data
should be sent to those pins using virtualWrites. Examples for sending and receiving
Virtual Pin data are under the Basics folder.
*/
//#define CAYENNE_DEBUG // Uncomment to show debug messages
#define CAYENNE_PRINT Serial // Comment this out to disable prints and save space
#include <CayenneWiFi.h>
// Cayenne authentication token. This should be obtained from the Cayenne Dashboard.
char token[] = "AuthenticationToken";
// Your network name and password.
char ssid[] = "NetworkSSID";
char password[] = "NetworkPassword";
void setup()
{
Serial.begin(9600);
Cayenne.begin(token, ssid, password);
}
void loop()
{
Cayenne.run();
}
Also, we need to know the specific model number of the Wifi shield as there are many of them, plus a few Chinese copies 
Cheers,
Craig
R3 Arduino Shield WiFi-Shield 65198 90-A2-DA-0F-A9-
Thats the information on the Shield.
Was my mistake by the copy , skatch is the same .Tried and on the dashboard : waiting for board to connect
I used it before with usb serial connection and that was ok but with wifishield no connection to dashboard maybe this is the problem
I have read that you may want to try a better quality USB cable or external supply with these boards.
Also, there is a known issue as well with the firmware, and perhaps the way you set the server. I’ll see if I can find a workaround if an external supply does not work.
Cheers,
Craig
I connected the arduino with a 12 V power supply , but didn´t work. .
The firmware from the wifi shield? Which server you mean?
Yeah, the shield firmware. How old is it?
How you pass the Cayenne server address to the begin function is what I was talking about. I’m not sure the Cayenne lib does that overload though.
See here:
Craig
I don´t know the exact prduction date of the shield on the board is no date but bought it for one week from a big electro shop .
I use an new USB cable , use additional 12 v power supply .
I installed arduino IDE , cayenne library . Then I took the sketch for WiFISHIELD from cayenne homepage changed only the token ,wifi name and password. uploaded the sketch . Then I saw what serial monitor told me. And everytime :
[[490] Connecting to FRITZ!Box6490Cable…
[10492] My IP: 192.168.177.46
[10492] Connecting to arduino.mydevices.com:8442
[21510] Connecting to arduino.mydevices.com:8442
[31513] Connecting to arduino.mydevices.com:8442
…
I read the link which you posted but everything I tried didn´t work. 
Don´t know what I did wrong
I tried it with an Raspberry 3 B and this works , so it must be something on the arduino
Good that you were able to connect. Raspberry Pi uses a different server and port though.
Either the board is goofy or you still have network blocking issues around 8442.
Can you try connecting your Uno using the standalone serial sketch. This will see your pc connecting to 8442 instead. Is your PC on wifi, or plugged into your router?
Cheers,
Craig
I tried it with arduino mega and arduino leonardo . serial usb connection is possible but with the wifishield no connection to mydevice server. I think the problem is the port because I have a Dual Stack light router connection, but can´t imagine why there are no problems with raspberry port .