Hp Officjet 4620 error message when scanning

Question

Hello,
I am using OSX Yosemite om an Imac and an Officjet 4620 printer. The printer is connected to the internet and printing and eprint works fine. Instead, when I try to scan this error message appears: "The scan could not be completed. Connection to the computer has been lost or the OCR application is not installed in the computer". I already followed some of your suggestios (uninstalled hp software, repaired disk permission, reinstalled software) but the error message persists.
Please help me!
Best
Luca

Answer 1

Hey @lucaborsari,
Welcome to the HP Support Forums!
I understand that you have an Officejet 4620 All-in-One installed through the network on your Mac OS X Yosemite system. I'd be happy to work with you in getting your scanner up and running properly. Thanks for letting me know that you have already run through a lot of key troubleshooting steps such as uninstalling, reinstalling and repairing the disk permissions. I'm sorry that these steps did not resolve the issue for you. Lets take a look at some additional troubleshooting steps to get this up and running for you.
Step 1: Check to see if other users are using the scanner:
Check with other users on your network to see if they are currently using the scanner. If so, wait until they are finished and have closed the scanning session.
Step 2: Try using the Scan feature on the computer:
Method 1: Scan with HP Scan Software:
Go to Macintosh HD/Applications/Hewlett-Packard, and then double-click the HP Scan icon.
Click Scan in the upper right corner of the window.
Click the Down arrow () to view and change any scan settings.
Click on Show Details to make any changes to the Presets.
To save any scan settings for a future scan job, click the pop-up menu next to Presets, click Save as, name the new preset, and then click OK.
Click Continue to start the scan.
When the scan completes, click Done.
To edit the scanned item, use the tools at the bottom of the window, and then click Send to either save it to a folder on your computer or to print the item.
Method 2: Scan with HP Utility:
Open HP Utility from the Dock.
Under Scan Settings, click Scan to Computer.
Click the Edit Scan Tasks button.
Select any presets that apply to your scan job.
Click the Edit button, change any desired settings, and then click Save.
To start the scan, click Test.
Scanning with the Full Feature HP Software in OS X v10.10 Yosemite
Does the product scan fine through the HP Scan software on the computer verses the Front Panel Scan options on the printer?
Step 2: Check the Scan to Computer setting:
On the main menu, click the Apple icon (), and then click System Preferences.
Click Print & Scan.
Under Printers, click your printer, if you see more than one printer.
Click Open Print Queue. The print queue for your printer opens.
Click Printer Setup or Settings. A new window opens.
Click the Utility tab, and then click Open Printer Utility. The HP Utility window opens.
Under Scan Settings, click Scan to Computer.
At the top of the screen, click the check box next to Enable Scan to Computer, if it is not already checked. Scan to Computer is enabled.
Try the scan again.
These steps can all be found in:
A 'No Computer Detected' or 'Connection Error' Message Displays When Scanning
Step 3: Check for Apple Software Updates: 
Select the Apple Menu
Select Software Update
Install any available updates
Try to scan again
Step 4: Powercycle the Network:
Unplug the power cable for your router for at least 30 seconds
While router is unplugged, power off your printer and  your computer
Plug in your router
Turn on your Printer
Turn on your Computer
Try to scan again
Please let me know if any of these steps help to resolve your scanning issue. Should they not fix your issue please let me know if the error 'The scan could not be completed. Connection to the computer has been lost or the OCR application is not installed in the computer' only occurs through Front Panel Scanning or if it also occurs while using the HP Scan Software on the Mac.
Good luck!
X-23
I work on behalf of HP
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