Why is my OctoPrint-powered printer offline?

This guide helps troubleshoot why your OctoPrint-connected printer shows offline in SimplyPrint.

OctoPrint typically runs on a Raspberry Pi connected to your printer via USB. SimplyPrint connects through the SimplyPrint plugin installed in OctoPrint.

Start here: Where is the problem?

Step 1: Can you access OctoPrint?

Open OctoPrint in your browser (usually http://<pi-ip-address>).

• Can't access OctoPrint? → Raspberry Pi issues
• Can access OctoPrint? → Continue to Step 2

Step 2: Is your printer connected in OctoPrint?

Look at OctoPrint's connection panel.

• Printer disconnected in OctoPrint? → This is a USB issue, not SimplyPrint. See USB and cable issues
• Printer connected in OctoPrint but offline in SimplyPrint? → SimplyPrint plugin issues

Note: SimplyPrint shows the same connection status as OctoPrint. If disconnected in OctoPrint, it will be offline in SimplyPrint.

Quick reference

2. SimplyPrint plugin issues

If your printer is connected in OctoPrint but offline in SimplyPrint, check the plugin.

Is the plugin enabled?

1. In OctoPrint: Settings (wrench icon) > Plugin Manager
2. Find "SimplyPrint Cloud"
3. Make sure it's enabled (not grayed out)

Is OctoPrint in Safe Mode?

Safe Mode disables all plugins. If you see "Safe Mode" in the title:

1. Click the power icon
2. Select "Restart OctoPrint" (not safe mode)
3. Wait for normal restart

Is the plugin up to date?

Settings > Software Update - check for SimplyPrint updates.

Check internet connection

The Pi needs internet access. If OctoPrint works locally but SimplyPrint is offline, check your network.

3. USB and cable issues

If your printer is disconnected in both OctoPrint and SimplyPrint, the problem is between OctoPrint and your printer.

First: Try power cycling your printer (turn off, wait 30 seconds, turn on).

3.1 USB cable problems

Important: 9 out of 10 connection issues are caused by the USB cable.

USB connector types:

Tip: A short, quality USB cable often fixes connection problems. Cables with ferrite cores (cylindrical bumps) help reduce interference.

3.2 Prusa printers: RPi port setting

Prusa MK3, MK3S, MK3S+, or Mini users: Check this setting!

Prusa printers have an "RPi port" setting that blocks normal USB connections.

To fix:

1. On printer screen: Settings
2. Find RPi port
3. Set to off

3.3 Other USB fixes

• Try a different USB port on the Pi
• Remove USB hubs - connect directly
• Power cycle the printer
• Remove SD card from printer

4. Raspberry Pi issues

4.1 Power supply

Bad power causes random disconnections.

Signs of power problems:

• Lightning bolt icon in OctoPrint
• Random disconnections
• Pi freezing or rebooting

Fix: Use official Raspberry Pi power supply (5V, 3A for Pi 4). Avoid phone chargers.

4.2 Can't access OctoPrint?

1. Wait for Pi to finish booting (few minutes after power on)
2. Check you're on the same network
3. Try pinging: ping <pi-ip-address>

4.3 Recommended Pi models

Works well:

• Raspberry Pi 4B (2GB+)
• Raspberry Pi 5
• Raspberry Pi Zero 2 W

Not recommended:

• Raspberry Pi Zero W (original) - too slow
• Raspberry Pi 2 - underpowered

Getting help

Gather this first

1. OctoPrint version
2. SimplyPrint plugin version
3. Raspberry Pi model
4. Printer model
5. Screenshot of OctoPrint connection panel

Support

• SimplyPrint Discord: simplyprint.io/discord
• OctoPrint Community: community.octoprint.org (for OctoPrint-specific issues)

Something unclear or missing in this guide? Let us know on Discord.

Related articles

• Which cable to use for SimplyPrint / OctoPrint
• Pick the right Raspberry Pi
• Prusa printer keeps disconnecting