Ok great madalina, and thank you for all the information. Let's go ahead first and unplug the USB, we will then start uninstalling the Lexmark software on the Compaq. I would like you to go ahead and start with the steps listed below:
1. Disconnect the USB Cable (where applicable).
2. Locate the Start / Programs / Lexmark XXXX Series / Tools / Uninstall Lexmark XXXX Series shortcut.
Note: The path may slightly vary for newer models; i.e. Start / Programs / Lexmark / Lexmark XXXX Series / Uninstall Lexmark XXXX Series shortcut.
3. To start the uninstallation procedure click on the Yes button.
Important! For newer models installed on Microsoft Windows Vista, 7, and 8, a User Account Control (UAC) for Lexmark International Inc. will pop up. Click Yes to allow uninstallation.
4. Please be patient and let the operation complete.
5. As indicated on the last screen, restart the computer by clicking OK.
NOTE: The uninstaller window interface may slightly vary per printer model, but serves the same purpose. This procedure removes only the core drivers (minimal print and scan drivers) and supporting software. The rest (OCR software, Fax Solution, Toolbar, etc.) have to be uninstalled separately.
Once you have uninstalled the software and have restarted the computer I would like you to go into your control panel and pull out any software and drivers associated with the Lexmark printer, take a look here on How to uninstall on Windows 7 from the control panel.
Now we will go to your Device Manager and make sure that the USB is not still being recognized under other devices, follow the steps listed below:
Start Menu> Search "Device Manager" > Check under the 'Printers' and remove the Lexmark if you see it there and check and see if you have 'Other Devices' and pull out Lexmark if it is listed in there.
Please let me know that these troubleshooting steps were done successfully so we can start with the installation. NOTE: Do not plug in the USB until advised.
I will watch for your reply.
Thank you,