Yes that's it. The block is only a cash in the sketch. Deleting the sketch solves the issue as does deleting the block then reopening the part.

Thanks

Hi, Thanks for the quick reply. But that's not quite what I'm talking about. I'm talking about the imbedded block. The command you have shown will delete the block from the sketch but not the part. For example if you edit the <dxf text-6> block and then delete it, then re-drag the original DXF file ...

Working in a part file I edit a sketch and drag a DXF file into the sketch. Solidworks makes the DXF file into Block and imbeds it into the part file.
How do I delete the block from the part file?