That's a bit drastic. He will lose all views, viewport setups, UCSs, unused
styles and blocks.
The problem is more likely much simpler to solve. Check that floating
viewports do not have the offending layers frozen in them before you purge.
If that doesn't work, look into your block definitions. Some may have had
these layers "current" when they were made, so that even if there were no
entities on these layers, they are defined in these blocks. For that matter
see if there are blocks you can purge, they may contain the block
One more thing, if the layers came in with an XREF they cannot be purged in
the host drawing.
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