Version 4.0 changed how Polymer retrieves data from OctoPrint. If the webcam, file list, and controls work, but printer information is not loading, see Troubleshooting Socket Connections.
Below are some commonly-encountered causes of connectivity problems and their solutions:
|The iOS device running Polymer is on a separate Wi-Fi network from the OctoPrint instance, or is connected to cellular data, resulting in it being unable to reach the OctoPrint instance.||Connect your iOS device to the same Wi-Fi network that your OctoPrint instance or set up remote access|
|The iOS device running Polymer is connected to a VPN.||Disable the VPN|
|Polymer is unable to connect to a SSL-protected OctoPrint instance using a self-signed certificate.||Install the custom SSL certificate on your iOS device and enable full trust in the Settings app, under ‘General’ → ‘About’ → ‘Certificate Trust Settings’|
|Polymer is unable to connect using the Ngrok Tunnel plugin||Ensure that ‘Enable Cross Origin Resource Sharing (CORS)’ is enabled and restart OctoPrint (see here)|
|Some network configurations cause Bonjour/zeroconf hostnames ( ||Use a direct IP address (e.g. 192.168.1.21 instead of octopi.local)|