<SUBMISSION>
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<PERIOD>20031024
<FILING-DATE>20031024
<REPORTING-OWNER>
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<CONFORMED-NAME>HARCZAK HARRY J JR
<CIK>0001215333
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<FILM-NUMBER>03957031
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<BUSINESS-ADDRESS>
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<CITY>LINCOLNSHIRE
<STATE>IL
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<PHONE>8474656000
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<CONFORMED-NAME>CDW CORP
<CIK>0000899171
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<IRS-NUMBER>363310735
<STATE-OF-INCORPORATION>IL
<FISCAL-YEAR-END>1231
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<BUSINESS-ADDRESS>
<STREET1>200 N MILWAUKEE AVE
<CITY>VERNON HILLS
<STATE>IL
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<PHONE>8474656000
</BUSINESS-ADDRESS>
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<STATE>IL
<ZIP>60061
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<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>CDW COMPUTER CENTERS INC
<DATE-CHANGED>19930322
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