Layer's On Off Problem

In my layer manager I see maybe 150 layers. I want to turn them all on. I click in the name area, do Control A to highlite all the layers, click on "ON", and only about two thirds of the layers are "ON". Shouldn't that turn them all on? None of the layers that are still "OFF" are frozen or locked.

Glenn

2009LT

Might the layers that are still "OFF" be layers that are not used? i.e. layers without any objects on them

Might the layers that are still "OFF" be layers that are not used? i.e. layers without any objects on them

OK, here's what happened. In the layer mgr, the "x-ref layers" were the one's showing in the list under filters. I don't have the x-ref. It's a customer sent drawing and they didn't bind or e-transmit the file. I clicked on "all used layers" and now I can work on the original question. The ON/OFF button doesn't seem to work when I select all the layers with Control A. In fact, I have them all turned off now, and I can't get them back on, unless I click on each layer one at a time.

Actually, all I see it doing is flipping the list from top to bottom, back and fourth.

JUst tried this in a small drawing I did in the past with ten layers. Simple drawing. Same results. I guess it's that acad LT thing again. Oh well.