Unable to delete model

[bhasse]

Does anyone have any idea about why I am not able to delete a model?  For some reason the model was duplicated and now I can't delete either one.  Also when I click on the model in the preview window to move it then "handles" to move and resize it are red.  Every other model that I am able to move, resize, or delete has blue handles.

[algerdes]

Did you accidentally lock the model? Right click on the model in question, choose "unlock". 
A locked model has red corner markers.  Not sure if anything else does, or not.