Problem loading roll paper on DesignJet 510 42

[dndFire]

Getting this error: Roll right edge too far from load line

Loading roll paper the same as we have for years, the paper is loaded properly but it still shows the message while trying to load it.

Tried cleaning the printheads which fixed the problem temporarily, but now even doing that isn't helping.  Figure it must be some sort of sensor issue where the paper is not being scanned in the right place (even though it is).

Can't find any troubleshooting for what part (if any) might be at fault.

[davidzuts]

Using a damp cloth gently clean the encoder strip that runs through the carriage assembly. Do not rub hard as you can remove the lines that the carriage reads. Pay close attention to the area on the right side over the service station and to the left of it as that is where ink can build up and block out some of the lines. Again do it gently.

[Jorge70]

Hi.
You must check blue line in rigth side on the plotter paper plate. If this is dirty then clear this one. If no dirty then check the encoder line or check de paper sensor in the carriage assy.
I hope helps