Velodyne sometimes error when launch the viewing data file

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Hallo, I am the new user of velodyne. Everything was fine when I tried the getting started with velodyne vlp 16 here http://wiki.ros.org/velodyne/Tutorial...

I connect the velodyne to sbc with ubuntu 1.04 with ros kinetic.

but these days sometimes I got the failed to load nodelet warning, and I don't know what this warning means, and how to solve it. I couldn't attach the picture here, but the warning says:

and there is also warning said that I have to read the web "http://eigen.tuxfamily.org/dox-devel/..."

is anybody have an idea about it? Thank you.