If your printouts look grainy or blurry, or you see light or dark horizontal banding, you may need to align the print head.
Note:
Banding may also occur if your cartridges are low on ink or you need to clean the print head.
Macintosh OS X: Open the Applications folder and select EPSON Printer Utility. Select your Epson Stylus CX7800 in the printer list, click OK, and select Print Head Alignment.
If you can't find an aligned pattern, choose the one that's closest to being aligned. Click Realignment and then Print to print another alignment sheet and repeat this step.
If you can't find an aligned pattern, choose the one that looks the best. Then click Realignment to print another alignment sheet and repeat this step.
If you can't find an aligned pattern, choose the one that looks the best. Then click Realignment to print another alignment sheet and repeat this step.