Please direct your media and public relations inquiries to: mediarelations@cdw.com 800-800-4CDW CDW To Announce May Sales on June 14, 2004 VERNON HILLS, Ill. - June 8, 2004 - CDW Corporation (Nasdaq: CDWC), a leading provider of technology products and services to business, government and education, today announced a change in the date for the announcement of its sales for May 2004. In recognition of stock markets' plans to be closed on Friday, June 11, 2004 for the national day of mourning in honor of President Reagan, the announcement of sales for May 2004 will be moved from Friday, June 11, 2004 to Monday, June 14, 2004. About CDW CDW® (Nasdaq: CDWC), ranked No. 376 on the FORTUNE 500, is a leading provider of technology products and services for business, government and education. CDW is a principal source of technology from top name brands such as APC, Apple, Cisco, HP, IBM, Microsoft, Sony, Symantec, Toshiba and ViewSonic. CDW distributes contracts to end users for customized and standardized on-site services supplied directly by providers such as HP Services and Unisys and for training programs provided by firms such as KnowledgeNet and Productivity Point International. CDW was founded in 1984 as a home-based business and today employs approximately 3,700 coworkers. In 2003, the company generated net sales of approximately $4.7 billion. CDW's direct model offers one-on-one relationships with knowledgeable account managers; purchasing by telephone, fax, the company's award-winning CDW.com Web site, customized CDW@work™ extranets, CDWG.com Web site and macwarehouse.com Web site; custom configured solutions and same day shipping; and pre- and post-sales technical support, with more than 100 factory-trained and A+ certified technicians on staff. Additional information can be found by visiting CDW.com.