Substantial resources are required for redefining product lines in order to sell online. Upgrading computer systems, training personnel, and updating websites requires substantial resources. Moreover, Electronic Data Management (EDM) and Enterprise Resource Planning (ERP), necessary for ensuring optimal internal business processes, may be looked upon, by some firms, as one of its disadvantages.
Read more at Buzzle: http://www.buzzle.com/articles/advantages-and-disadvantages-of-e-business.html