INSERT command fails to create block insertion

I'm trying to insert a block into a drawing using the INSERT command. The block is a .dwg file called "ElevStairsB2E2S4.dwg." I invoke the INSERT command, use the "Browse" button to navigate to the file, and click OK, then I give the insertion point (0,0), and nothing appears. There is no error message about duplicate block names, etc. Investigating this with AutoLISP at the command prompt,

(tblsearch "block" "ElevStairsB2E2S4")

returns

((0 . "BLOCK") (2 . "ElevStairsB2E2S4") (70 . 0) (10 0.0 0.0 0.0) (-2 . <Entity
name: 7fff64638d0>))

indicating that the block definition has been added to the drawing's symbol table. But even after additional attempts with INSERT,

(setq a (ssget "X" '((0 . "INSERT") (2 . "ElevStairsB2E2S4"))))

returns nil, indicating there are no insertions of the block in the drawing. And invoking QSELECT, and selecting "Block Reference" and "Name", the block name "ElevStairsB2E2S4" does not appear in the drop-down list, also indicating there are no insertions of it in the drawing.

Attempting to use COPYBASE to insert the objects from ElevStairsB2E2S4 into the host drawing also fails, with no error message. This simply results in no objects being copied into the host drawing.

How can I get ElevStairsB2E2S4 into my drawing? Please advise.

Thanks,

Michael Evans

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