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<PERIOD>20030626
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<REPORTING-OWNER>
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<CIK>0000942499
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<FILE-NUMBER>000-21796
<FILM-NUMBER>03759195
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<CITY>NORTHBROOK
<STATE>IL
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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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<STREET1>200 N MILWAUKEE AVE
<CITY>VERNON HILLS
<STATE>IL
<ZIP>60061
<PHONE>8474656000
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<MAIL-ADDRESS>
<STREET1>200 N MILWAUKEE AVE
<CITY>VERNON HILLS
<STATE>IL
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<FORMER-CONFORMED-NAME>CDW COMPUTER CENTERS INC
<DATE-CHANGED>19930322
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<?xml version="1.0"?>
<ownershipDocument>
    <schemaVersion>X0101</schemaVersion>

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    <issuer>
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            <rptOwnerStreet2>  </rptOwnerStreet2>
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            <rptOwnerZipCode>  </rptOwnerZipCode>
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