Who is the only US President that did not pass any Executive Orders during his days in office?

Executive Orders (EOs) are legally binding orders given by the President, acting as the head of the Executive Branch, to Federal Administrative Agencies. Executive Orders are generally used to direct federal agencies and officials in their execution of congressionally established laws or policies.

Harrison was only in office for 31 days. On March 26, Harrison became ill with a cold. His extremely busy social schedule made any rest time scarce.

Harrison's doctors tried cures, applying opium, castor oil, leeches, and Virginia snakeweed, but the treatments only made Harrison worse, and he became delirious. He died nine days after becoming ill, at 12:30 am on April 4, 1841. Harrison's doctor, Thomas Miller, diagnosed Harrison's cause of death as "pneumonia of the lower lobe of the right lung", but a 2014 medical analysis concluded that he instead died of enteric fever. The authors base their findings on the president's symptoms and the close proximity of the White House to a dumping ground for sewage and human waste.He was the first United States president to die in office.

https://en.wikipedia.org/wiki/William_Henry_Harrison