Given it's a US federal dataset at its root and given some of the issues with data at that level over the last several months, is it possible the source data is down and/or otherwise unavailable?
I can't quite remember if the Explorer is an ESRI-hosted mirror or if it's polling directly from the NLCD source, at the moment.
------------------------------
M Reed
"The pessimist may be right oftener than the optimist, but the optimist has more fun, and neither can stop the march of events anyhow." — Lazarus Long, in Time Enough for Love, by Robert A. Heinlein
