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PAGE 2
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PAGE 3
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PAGE 4
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PAGE 7
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PAGE 9
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SIGNATURE JAMES M. ROY
TITLE V.P. AND C.F.O.
EXHIBIT INDEX TO FORM N-SAR
OF MASSMUTUAL CORPORATE INVESTORS
FOR ANNUAL PERIOD ENDED DECEMBER 31, 2007
EXHIBIT NO. DESCRIPTION
77B Accountant's Report on Internal Controls
77O Transactions Effected Pursuant to Rule 10f-3
77Q2 Information called for by Item 405 of Regulation S-K