Converting .dwg to .vsd

[cldh00]

I have a .dwg file that I need to use within Visio. I open up the .dwg file within Visio and then highlight the entire diagram. From here, I right click on the diagram, click CAD Drawing Object, then Convert. From here, I select the layers that I need to convert, then click Next. The next option I choose is to Delete Selected DWG Layers and then click Next. The last 2 bullets I have checked are Convert Into Visio’s Dimension Shapes and also Convert Every Hatch Line In The Pattern into Visio Shapes. Now, the conversion is done. Next, I have the entire diagram selected once again and right click Shape and select Ungroup. However, from here, I receive an error message that says:
"An error (1411) occurred during the action Ungroup.
There was an error reading or writing OLE data."
Any ideas?
Chad