Your HP OfficeJet Pro 9120e prints fine but the scanner just sits there. You press Scan and nothing happens. Or the file never reaches your computer. Or the automatic document feeder keeps grabbing two pages at once. The 9120e is HP's 2023 all-in-one with Wi‑Fi 5, Ethernet, USB, AirPrint, and the HP Smart app, and scanning hiccups usually trace back to connectivity, software, or the scanner hardware itself.
The quickest fix is to confirm the HP Smart app is actually running on your computer or phone. Without that app active, the printer's scan‑to‑computer button doesn't know where to send the file. Open HP Smart, tap the scan icon, and try again. If it connects, you're done in seconds.
If that didn't do it, work through the rest in order.
Why the Scanner Stopped Working
The OfficeJet Pro 9120e supports scan‑to‑computer (USB or Wi‑Fi), scan‑to‑email (via SMTP), and scan via AirPrint or the HP Smart app. Each method has its own failure points:
- HP Smart not running or not installed: scan‑to‑computer needs the app active on the destination device.
- Driver or firmware outdated: HP pushes fixes for AirPrint and scanning, but only if you install them.
- Network connection dropped: the printer may still print via a stale connection, but scanning won't work.
- Wi‑Fi security mismatch: WPA3‑only SSIDs can block the 9120e from pairing, and scanning dies too.
- AirPrint disappeared after a firmware update: a known issue that requires a re‑add.
- Scan‑to‑email SMTP credentials expired: Gmail and Outlook regularly invalidate app passwords stored on the printer.
- Firewall or security software blocking HP Smart: Windows Defender or third‑party suites often quarantine scanning traffic.
- Computer went to sleep: the printer can't push the scan file to a sleeping machine.
- ADF roller dirty: dust causes double‑feed jams in the automatic document feeder.
- Scanner glass smudged: dark lines or blank scans often mean a dirty scan bed.
Make Sure HP Smart Is Actually Running
On Windows, look for the HP Smart icon in the system tray. On a Mac, check the menu bar. On your phone, open the app fresh from the home screen. If it's not visible, launch it from the Start menu or Applications folder.
With HP Smart open, walk to the printer and press the Scan icon on the touchscreen. Choose Scan to Computer and select your device. The file will land in the HP Smart scans folder by default. If the computer doesn't appear in the list, the app isn't listening, restart the app and try again.
Whitelist HP Smart in Your Firewall
HP's own support docs flag this as a leading cause: Windows Defender Firewall or antivirus suites block the scanning traffic, and the printer can't show you an error. On Windows, go to Windows Security > Firewall & network protection > Allow an app through firewall. Find HP Smart and HP Scan in the list. Make sure both Private and Public boxes are checked. If they aren't listed, click Allow another app and browse to C:\Program Files\HP\HP Smart\ or similar.
If you use Norton, McAfee, or another security suite, add HP Smart to the allowed apps there as well. Restart the computer and test the scan.
Reset the Network Connection on the Printer
The OfficeJet Pro 9120e has a handy network‑only reset that keeps your other settings intact. Press and hold the Wireless and Cancel buttons together for about 5 seconds. The printer will cycle its wireless radio and drop any stale connection. Wait for the Wi‑Fi light to stabilize, then reconnect via the HP Smart app.
If you're still having trouble, go to the touchscreen: swipe down to open the dashboard, tap the gear icon for Setup, then Tools > Restore > Restore Factory Defaults. That wipes all network settings and enrollment, so only do it if the network reset doesn't help.
Switch to a Mixed WPA2/WPA3 Network
The 9120e supports both 2.4 GHz and 5 GHz bands, but it has trouble pairing on WPA3‑only SSIDs. If your router is set to WPA3‑only (or you see "Protected Management Frames" enabled), temporarily switch to WPA2‑Personal or WPA2/WPA3 mixed mode during setup. Many mesh networks default to WPA3, which can cause the printer to stall during initial pairing. Once the printer is connected, you can usually switch back to WPA3, the scanner should keep working.
Update the Firmware via HP Smart
HP periodically releases firmware updates that fix scanning glitches, including the well‑known bug where AirPrint disappears after an update. Open the HP Smart app on your computer or phone, tap the printer icon, and check for updates. If one is available, let it install. The printer may reboot once or twice. After the update, re‑add AirPrint (if using iOS) or try scanning from HP Smart again.
Reinstall HP Smart and the Scan Driver
If nothing else works, remove the software and start fresh. On Windows, go to Settings > Apps > Installed apps, find HP Smart and HP Scan, and uninstall. Reboot the computer. Then download the latest HP Smart app from HP's official site. On Mac, drag the HP Smart app to Trash and run the HP uninstaller tool. Reinstall from the App Store or HP's site.
After reinstalling, open HP Smart and let it discover your 9120e. The fresh driver registration usually clears those stubborn "printer not found" errors.
Fix Scan‑to‑Email SMTP Credentials
If you use scan‑to‑email with Gmail, Outlook, or another provider that requires 2FA, the app password saved on the printer may have expired. Generate a new one: in Gmail, go to Google Account > Security > 2‑Step Verification > App passwords. Create one for "Other" and copy it. On the printer touchscreen, go to Setup > Web Services > Email > SMTP Settings and update the password. Test by scanning a single page to yourself.
Wake the Computer Before Scanning
Scan‑to‑computer pushes the file from the printer to a host that has to be awake and running HP Smart. If your laptop is asleep, the scan job hangs silently. Wake the computer fully, make sure HP Smart is active on screen, then press Scan on the printer.
Use a Wired Connection for Reliable Scans
The OfficeJet Pro 9120e has a USB‑B port and an Ethernet port. If you're scanning large multi‑page documents over Wi‑Fi and they keep failing, switch to Ethernet. Plug a Cat 5e or better cable from the printer to your router. The printer picks up an IP within 30 seconds. Then re‑add the scanner in HP Smart using the Ethernet IP. Large scans will complete without timeouts.
Clean the Scanner Glass and ADF Roller
Dark lines, streaks, or blank scans usually mean the scanner glass is dirty. Lift the scanner lid and wipe the glass with a lint‑free cloth slightly dampened with distilled water. For the ADF, lift the ADF cover (the flap on top) and locate the rubber pickup roller. Wipe it gently with a cloth dampened with water. Let everything dry for a minute before closing.
If the ADF still double‑feeds, you might have paper dust inside. Run a clean sheet of uncoated paper through the ADF a couple of times to dislodge debris.
Lower the Scan Resolution
Scanning a full page at 1200 DPI can take several minutes and may time out over Wi‑Fi. For text documents, 300 DPI is plenty (and works fine for OCR). For photos, 600 DPI is usually enough. In HP Smart, tap the scan settings and lower the resolution before starting a large batch.
