Step 1 ![](https://publications.lexmark.com/media/ids_assets/images/transparent.png) Depending on your operating system, specify the paper type, texture, and weight from the Printing Preferences or Print dialog. Notes: - Make sure that the settings match the paper loaded in the tray.
- You can also change the settings on the printer control panel.
![](https://publications.lexmark.com/media/ids_assets/images/transparent.png) Print the document.
Do vertical dark lines or streaks still appear on prints? | Go to step 2. | The problem is solved. |
Step 2 ![](https://publications.lexmark.com/media/ids_assets/images/transparent.png) Load paper from a fresh package. Note: Paper absorbs moisture due to high humidity. Store paper in its original wrapper until you use it. ![](https://publications.lexmark.com/media/ids_assets/images/transparent.png) Print the document.
Do vertical dark lines or streaks still appear on prints? | Go to step 3. | The problem is solved. |
Step 3 ![](https://publications.lexmark.com/media/ids_assets/images/transparent.png) Inspect the test pages to determine which color is affected. ![](https://publications.lexmark.com/media/ids_assets/images/transparent.png) Remove, and then reinstall the photoconductor unit. Warning—Potential Damage: Do not expose the photoconductor unit to direct light for more than one minute. Extended exposure to light can cause print quality problems. Warning—Potential Damage: Do not touch the photoconductor drum. Doing so may affect the quality of future print jobs. ![](https://publications.lexmark.com/media/ids_assets/images/transparent.png) Print the document.
Do vertical dark lines or streaks still appear on prints? | Go to step 4. | The problem is solved. |
Step 4 ![](https://publications.lexmark.com/media/ids_assets/images/transparent.png) Clean the printhead lens. ![](https://publications.lexmark.com/media/ids_assets/images/transparent.png) Print the document.
Do vertical dark lines or streaks still appear on prints? | Go to step 5. | The problem is solved. |
Step 5 ![](https://publications.lexmark.com/media/ids_assets/images/transparent.png) Inspect the test pages to determine which color is affected. ![](https://publications.lexmark.com/media/ids_assets/images/transparent.png) Replace the photoconductor unit. ![](https://publications.lexmark.com/media/ids_assets/images/transparent.png) Print the document.
Do vertical dark lines or streaks still appear on prints? | Contact customer support. | The problem is solved. |