1. Click the Windows “Start” button and double-click on “Computer.” Double click on the “C:” drive and then click on the “Program Files” directory. Click on the 'Lexmark' subdirectory – the name will vary depending on your printer model number.
2. Find the “aioc_app.ini” file and right-click on it. Click “Cut” from the context menu and then right-click on another directory such as “Documents.” Click “Paste” to move the selected file to a different location.

3. Click the “Start” button. Click “Programs.” Locate and click on the “Lexmark All-in-One Center” icon. The software should load without reporting the AIOC.exe error and all features should be functioning correctly.
4. Right-click on the “aioc_app.ini” file and click “Cut.” Right-click inside the “Lexmark” directory where the file was previously located and click “Paste” to move the file back to the original folder.
5. Start the “Lexmark All-in-One Center” software again to confirm that the issue has been resolved. If not, remove the “aioc_app.ini” file entirely and reboot your computer.