Hello Carlos
Well of course, if your App attempts to download from anywhere on the Internet and there is no connection, that will trigger an error message. Generally speaking, as an App User, you would want that information so that you could then do something to fix it, such as enabling a WiFi or Data connection.
We would need to see your blocks, but I'm guessing you get constant error messages because your app is constantly trying to download? App Inventor can catch error messages, so you might like to try that if you don't want to keep the App User informed:
![ignore error message.png](https://groups.google.com/group/mitappinventortest/attach/3326c68dd79fb/ignore%20error%20message.png?part=0.1&view=1)