Epson 1010 User Manual page 187

Vertical printed lines do not align
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The printer is usually set for bidirectional printing. This can
cause a slight misalignment of graphics characters. When precise
printing of vertical lines is necessary, contact your dealer to have
the bidirectional print alignment adjustment performed.
You can also select unidirectional printing by setting DIP switch
2-6 to off. Unidirectional printing is slightly slower.
If the printer still does not print, disconnect the printer from your
computer and try the self test described in Chapter 1. If the self test
works properly, the printer is working, and the problem probably
lies in the computer, the software, or the cable. If the self test does
not work or if any other problem persists, contact your dealer or call
the Consumer Information number listed in Where to Get Help.
7-6 Troubleshooting
gaps appear in lines or graphics.
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