**Exhibit 31.1**

 

**Certificationof Principal Executive Officer**

 

I,Bruce L. Claflin, certify that:

 

1.                                       I have reviewed this quarterlyreport on Form 10-Q of 3Com Corporation;

 

2.                                       Based on my knowledge, thisreport does not contain any untrue statement of a material fact or omit tostate a material fact necessary to make the statements made, in light of thecircumstances under which such statements were made, not misleading withrespect to the period covered by this report;

 

3.                                       Based on my knowledge, thefinancial statements, and other financial information included in this report,fairly present in all material respects the financial condition, results ofoperations and cash flows of the registrant as of, and for, the periodspresented in this report;

 

4.                                       The registrant’s othercertifying officer(s) and I are responsible for establishing and maintainingdisclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e)and 15d-15(e)) for the registrant and have:

 

(a)                                  Designed such disclosurecontrols and procedures, or caused such disclosure controlsand procedures to be designed under our supervision, to ensure that materialinformation relating to the registrant, including its consolidatedsubsidiaries, is made known to us by others within those entities, particularlyduring the period in which this report is being prepared;

 

(b)                                 [Paragraphomitted pursuant to SEC Release Nos. 33-8238 and 34-47986]

 

(c)                                  Evaluated the effectiveness ofthe registrant’s disclosure controls and procedures and presented in thisreport our conclusions about the effectiveness of the disclosure controls andprocedures, as of the end of the period covered by this report based on suchevaluation; and

 

(d)                                 Disclosed in this report anychange in the registrant’s internal control over financial reporting thatoccurred during the registrant’s most recent fiscal quarter (the registrant’sfourth fiscal quarter in the case of an annual report) that has materiallyaffected, or is reasonably likely to materially affect, the registrant’s internalcontrol over financial reporting; and

 

5.                                       The registrant’s othercertifying officer(s) and I have disclosed, based on our most recent evaluationof internal control over financial reporting, to the registrant’s auditors andthe audit committee of the registrant’s board of directors (or personsperforming the equivalent functions):

 

(a)                                  All significant deficiencies andmaterial weaknesses in the design or operation of internal control overfinancial reporting which are reasonably likely to adversely affect theregistrant’s ability to record, process, summarize and report financialinformation; and

 

(b)                                 Any fraud, whether or notmaterial, that involves management or other employees who have a significantrole in the registrant’s internal control over financial reporting.

 
| Date:  | January 12,  2004                                                           |   |   |
|--------|----------------------------------------------------------------------------------|--------|--------|
|   |                                                                             |
|   |                                                                             |
|   | /s/          BRUCE  L. CLAFLIN |   |
|   | Bruce  L. Claflin                                                                |
|   | President  and Chief Executive Officer                                           |

 

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