Verify that the source and target drawings are set to meters under the UNITS command.
Verify that the INSUNITS is set to 0 (or 4 for metric/millimeters, as long as both drawings are set to meter under UNITS).
Lastly, verify that OPTIONS>User Prefernces>Insertion Scale is set to Unspecified - Unitiless for both source and target (all that matters is that they are the same).
Where in the Block Editor would you reset a block's units?
Thanks, Matt. I didn't think about opening the Properties Palette inside the Block Editor.
Start with some of our most frequented solutions or visit the Installation and Licensing Forum to get help installing your software.