Error scanning the section. See long text

What causes this issue?

An error occurred when the section was scanned. This may have been
caused by a syntax error in this sectin. The class is in an
inconsistent state at present. That is, the metadata is not consistent
with the generated source. Resolve the syntax error from the section
and try again to remove the inconsistency.

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

System Response

How to fix this error?

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.