Loading json data from a file into Postgres

Try this:

BEGIN;
-- let's create a temp table to bulk data into
create temporary table temp_json (values text) on commit drop;
copy temp_json from 'C:\SAMPLE.JSON';

-- uncomment the line above to insert records into your table
-- insert into tbl_staging_eventlog1 ("EId", "Category", "Mac", "Path", "ID") 

select values->>'EId' as EId,
       values->>'Category' as Category,
       values->>'Mac' as Mac,
       values->>'Path' as Path,
       values->>'ID' as ID      
from   (
           select json_array_elements(replace(values,'\','\\')::json) as values 
           from   temp_json
       ) a; 
COMMIT;