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CONSENT OF ERNST & YOUNG LLP,
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
We consent to the incorporation by reference in the Registration Statements of Aon Corporation described in the following table of our reports dated March 9, 2005, with respect to the consolidated financial statements and schedules of Aon Corporation, Aon Corporation's management assessment of the effectiveness of internal control over financial reporting, and the effectiveness of internal control over financial reporting of Aon Corporation, included in this Annual Report (Form 10-K) for the year ended December 31, 2004.
Registration Statement | | |||
---|---|---|---|---|
Form | Number | Purpose | ||
S-8 | 33-27984 | Pertaining to Aon's savings plan | ||
S-8 | 33-42575 | Pertaining to Aon's stock award plan and stock option plan | ||
S-8 | 33-59037 | Pertaining to Aon's stock award plan and stock option plan | ||
S-3 | 333-50607 | Pertaining to the registration of 369,000 shares of common stock | ||
S-8 | 333-55773 | Pertaining to Aon's stock award plan, stock option plan, and employee stock purchase plan | ||
S-3 | 333-78723 | Pertaining to the registration of debt securities, preferred stock and common stock | ||
S-4 | 333-57706 | Pertaining to the registration of up to 3,852,184 shares of common stock | ||
S-3 | 333-74364 | Pertaining to the registration of debt securities, preferred stock, common stock, share purchase contracts, and share purchase units | ||
S-3 | 333-100466 | Pertaining to the registration as amended of 2,707,018 shares of common stock | ||
S-3 | 333-102799 | Pertaining to the registration of senior convertible debentures and common stock | ||
S-8 | 333-103344 | Pertaining to the registration of common stock | ||
S-8 | 333-106584 | Pertaining to Aon's deferred compensation plan |
ERNST & YOUNG LLP | |
Chicago, Illinois March 14, 2005 |
CONSENT OF ERNST & YOUNG LLP, INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM