Why has my macOS printer disappeared after a few hours?

I had the same problem, and here’s what worked for me:

1. Restart: First, try restarting both your Mac and your printer. A simple reboot can sometimes solve connectivity issues.

2. Update Software: Ensure your macOS and printer drivers are up to date. Periodic software updates can resolve such bugs.

3. Re-add the Printer: Go to System Preferences -> Printers & Scanners. Remove the printer and then add it again by clicking the plus button. This refreshes the connection.

4. Network Consistency: For network printers, verify the printer and your Mac are on the same network. Inconsistent network settings can cause the printer to disappear.

5. IP Connection: Instead of using Bonjour, add the printer using its IP address. This often leads to a more stable connection.

This issue can be a real headache. Here’s a detailed approach I took:

1. Conflict with Other Devices: I suspected a conflict. By turning off all other network-connected devices, I found my security camera shared the printer’s IP, causing intermittent drops.
2. Manual IP Change: I assigned a new IP to the printer through its control panel, which solved the conflict.
3. Printer Logs: Checking the logs through the printer’s web interface gave me exact reasons for disconnection.
4. Apple Support: When all else failed, Apple Support provided additional diagnostics and solutions.

From my experience, it’s most likely a software glitch. Here’s a quick checklist:

• Ensure Up-to-Date Software: Both macOS and printer drivers need to be the latest version.
• Remove and Reconnect: Often removing the printer in System Preferences and then adding it back resolves the issue.
• Network Connection: Ensure both devices are properly connected to the Wi-Fi.
• Use Alternative Connection Methods: If a wireless connection is unstable, consider using a USB connection.

A friend faced something similar and recommended these steps:

1. Remove and Reinstall: Sometimes, all you need to do is remove the printer from System Preferences and add it back.
2. Use Static IP: Setting a static IP for your printer can help maintain a stable connection.
3. Firmware Update: Make sure your printer firmware is up to date. This can resolve many issues.
4. Energy-Saving Settings: Adjust any energy-saving features on your printer to prevent it from going offline.

Here’s what worked for me in a less technical way:

1. Simply Restart Everything: Often a restart is all that’s needed. Try restarting your Mac and your printer.
2. Reconnect to Network: Double-check both devices are on the same Wi-Fi network, especially if they were powered off.
3. Driver Updates: Make sure to download the latest drivers from the printer’s official site. This solves many issues.
4. Re-add Printer: Go to System Preferences, remove, and re-add the printer. This can refresh the connection.

Facing this issue really puzzled me. What eventually fixed it was modifying the printer’s sleep settings:

• Printer Manual: I consulted the printer’s manual to access advanced settings. Energy-saving modes tend to disable wireless connectivity after a span of inactivity.

• Adjust Sleep Duration: I set the sleep duration to ‘Never’. This kept the printer continuously active.

• Static IP Address: Assigning a static IP to the printer helped stabilize the connection as the Mac could always link to the right address.

• Router Check: I also checked my router for IP conflicts. Some routers might block or complicate connections around specific IP ranges.