[Wim-T]

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My RX-4 receiver in "system info" gives a red icon for wunderground. (i did not change anything in software so far)

From what I can read on Cumulus Forum (thanks AllyCat for the link to the info) seems WU is currently having some issues.

I have two stations uploading to WU, at moment one is online (Green Icon on the RX) the other is offline (Red icon).

 According the information found on Wxforum  the  WU-site  say use the upload-key ! , but i always used the upload-key!
 Some had succes with the API-key i tryed but without succes.

Copy from WU-site ;
PWS Connection Information   Status: Current  Short Summary: 
If you are experiencing issues with your station not connecting, ensure you are using the upload key located on the My Devices page of Weather Underground (My Profile> My Devices. Look for the Station ID, the upload key is to its right.) So wherever you see “password” in your station set-up, use the upload key. This should bring the station back online. Note: this is not the same as an API key, which has a completely different purpose. Make sure you are using the “upload key” from the My Devices page and entering it where your uploading software calls for a “password”. Thanks for being part of the Weather Underground community!