Exhibit 99-B Certification of Chief Executive Officer Pursuant to U.S.C. Section 1350, as Adopted Pursuant to Section 906 of The Sarbanes-Oxley Act of 2002 I, Steven A. Raymund, Chairman of the Board of Directors and Chief Executive Officer of Tech Data Corporation ("Tech Data"), do hereby certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that, to my knowledge: (i) Tech Data's Annual Report on Form 10-K for the fiscal year ended January 31, 2003, (the "Report") fully complies with the requirements of Section 13(a) or Section 15(d), as applicable, of the Securities Exchange Act of 1934, as amended; and (ii) the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of Tech Data. Dated: April 24, 2003 /s/ Steven A. Raymund --------------------------------------- Steven A. Raymund Chairman of the Board of Directors and Chief Executive Officer