I have a polygon that represents a property boundary.
In our jurisdiction, one can't build in a 10m area within the entire boundary (a yard).
I want to create a polygon along that 10m line.
I've tried the trace and shrink tools, but they don't seem to create what I need.
I've tried searching for answers, but can't find them anywhere. Hence why I am posting here.
Use the tool Buffer.
For buffer distance, use a negative value (in your case -10 meters).
If you want to get the area where building is allowed, use Side Type "Full".
If you want to get the area where building is prohibited, use Side Type "Exclude the input polygon from buffer".
When I try to create a buffer I get the following message:
"Buffer: an unexpected failure occured
The spatial index grid size is invalid. (polygons)
the spatial index grid size is invalid."
"The feature(s) could not be buffered."
I have tried to recreate the spatial index but keep getting the same message.
I've followed the instructions at https://desktop.arcgis.com/en/arcmap/latest/manage-data/geodatabases/modifying-a-spatial-index.htm
Sadly, I can't suggest anything further than recreating the index. You probably should post that as a new question.