canon mg3620 power light is on but it won't print anything from my computer

Diagnosis

This issue typically manifests as a "Communication Error" or a "Printer Offline" status in Windows or macOS, despite the power light being solid. Because the power light is on, the hardware is receiving current, but the data handshake between the Canon PIXMA MG3620's wireless NIC (Network Interface Card) and your computer's print spooler has failed. This is most commonly caused by a dynamic IP address shift; your router assigned a new IP to the printer, but your computer is still trying to send data to the old, cached IP address. Alternatively, this can be a "Ghost Job" scenario where a corrupted print command is stuck at the top of the queue, blocking all subsequent documents. To confirm if the problem is communication or hardware, press the 'Stop' button on the printer. If the printer doesn't react or the Alarm lamp flashes a specific sequence (like 2 or 4 times), the issue is likely a localized hardware jam or ink error. If the printer seems responsive but the computer says "Offline," the breakdown is in the network handshake or the driver's port configuration.

How to Fix It

To resolve the communication break and clear the print pipeline, follow these exact steps:

1. Clear the Print Spooler: On your PC, press Windows Key + R, type services.msc, and hit Enter. Find "Print Spooler," right-click it, and select "Stop." Navigate to C:\Windows\System32\spool\PRINTERS and delete all files in that folder. Go back to the Services window, right-click "Print Spooler," and select "Start."
2. Reset the Network Handshake: Turn off the printer. Unplug your wireless router from the power source for 30 seconds, then plug it back in. Once the Wi-Fi is fully restored, turn the MG3620 back on.
3. Re-establish the Wireless Link: Press and hold the Wi-Fi button on the printer until the Power lamp flashes. Press the Stop button until the Alarm lamp flashes once, then release it. Press the Wi-Fi button again. The Wi-Fi lamp should stay lit, indicating a successful reconnection to the router.
4. Verify Port Settings (Windows): Go to Control Panel > Devices and Printers. Right-click the MG3620 and select "Printer Properties." Go to the "Ports" tab. Ensure "Canon MG3600 series" is checked. If it shows a "WSD" port and is offline, you may need to remove the device and re-add it using the "Add a printer" wizard to refresh the IP mapping.
5. Print a Nozzle Check: To ensure the hardware is ready, press the Stop button until the Alarm lamp flashes once, then press the Color or Black start button. If the pattern prints, the connection is restored.

If That Didn't Work

• Perform a Deep Cleaning: If the printer is "Printing" but the pages are blank, the print head is clogged. Press the Stop button until the Alarm lamp flashes twice, then press the Black start button. This initiates a more aggressive cleaning cycle than the standard one.
• Switch to USB Connection: Connect the printer via a standard USB-A to USB-B cable. If it prints immediately, the issue is 100% network-related. This allows you to update the firmware or drivers without fighting the wireless signal.
• Disable Firewall/Antivirus Blocking: Temporary disable Windows Defender or third-party software like Norton or McAfee. These often flag the Canon bidirectional communication port (usually Port 9100) as a security threat, blocking the print signal while leaving the power light on.
• Hard Reset the Printer: Unplug the power cord from the back of the MG3620 and remove the ink cartridges. Hold the power button down for 60 seconds to discharge the internal capacitors. Reinsert cartridges and plug the power back in.

Heads Up

• Avoid Generic Drivers: Always use the specific Canon MG3600 series driver rather than the "Generic Inkjet" driver provided by Windows Update; the generic version often fails to report "Offline" status correctly.
• Ink Level Warning: The MG3620 will sometimes refuse to send data to the print head if one of the cartridges is critically low, even if the power light is green. Ensure all ink levels are above the minimum line.
• Wi-Fi Frequency: This model only supports 2.4GHz Wi-Fi. If you have a dual-band router, ensure your computer isn't trying to force the printer onto a 5GHz band, which will cause intermittent "Offline" errors.