@JANBEN1947, Welcome to the HP Support Community!
Thanks for reaching out about your query regarding your red ink cartridge!
We're thrilled to have the opportunity to assist you and provide a solution.
It looks like you've already done a great job troubleshooting the issue. Since you're still seeing the error, let's try a few more steps:
Perform a Hard Reset
- With the printer turned on, unplug the power cord from the back.
- Unplug the power cord from the wall outlet.
- Wait at least 60 seconds.
- Plug the power cord back into the wall outlet first.
- Reconnect the power cord to the printer.
- Turn the printer back on and check if the error persists.
Check for Firmware Updates
Sometimes, outdated firmware can cause supply system errors.
- Go to HP support website.
- Enter your printer model (HP OfficeJet Pro 8740).
- Check for firmware updates for macOS 10.12 Sierra.
- If an update is available, download and install it.
Reset the Ink System
- Remove all ink cartridges.
- Power off the printer and unplug it for at least 10 minutes.
- Plug it back in and power it on.
- Reinstall the cartridges one by one, making sure they are securely in place.
Inspect for Internal Damage
- Check if the cartridge slot is damaged or has bent pins.
- Try inserting a different set of cartridges (borrow if possible) to rule out cartridge issues.
Disable Cartridge Protection
If your printer was previously used with another HP account, cartridge protection might be active.
- Open the HP Utility software on your Mac.
- Go to HP OfficeJet Pro 8740 settings.
- Look for an option to disable cartridge protection.
- Restart the printer and test again.
Let me know if any of these steps help!
Take care, and have an amazing day!
Did we resolve the issue? If yes, Please consider marking this post as "Accepted Solution" and click "Yes" to give us a helpful vote - your feedback keeps us going!
Regards,