cannot bring up layers dialog

I have just installed GIMP on my home computer, have been using it at work with no problems. On my home computer, I am unable to bring up the Layers, channels, etc. dialog. I have tried Ctrl+L, tried Windows>Layers..., don't know what else to try. The Toolbox shows up just fine. Any suggestions? I am new to GIMP, so don't really know where to start.