Exhibit 16.1 [Arthur Andersen LLP Letterhead] April 8, 2002 Office of the Chief Accountant Securities and Exchange Commission 450 Fifth Street, N.W. Washington, D.C. 20549 Dear Sir/Madam: We have read the second, third and fourth paragraphs of Item 4 included in the Form 8-K dated April 4, 2002 of Network Commerce Inc. to be filed with the Securities and Exchange Commission and are in agreement with the statements contained therein. Very truly yours, /s/ Arthur Andersen LLP