**Exhibit 31.1**

 

**CERTIFICATION**

 

I, Surendra Pai,****certify that:

 

1.             I have reviewed this Quarterly Report on Form 10-Q ofAuthentidate Holding Corp.;

 

2.             Based on my knowledge, this report does not contain anyuntrue statement of a material fact or omit to state a material fact necessaryto make the statements made, in light of the circumstances under which suchstatements were made, not misleading with respect to the period covered by this** **report;

 

3.             Based on my knowledge, the financial statements, andother financial information included in this report, fairly present in allmaterial respects the financial condition, results of operations and cash flowsof the registrant as of, and for, the periods presented in this report;

 

4.             The registrant’sother certifying officer(s) and I are responsible for establishing andmaintaining disclosure controls and procedures (as defined in Exchange ActRules 13a-15(e) and 15d-15(e)) and internal control over financial reporting(as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for theregistrant and have:

 

a)             Designed suchdisclosure controls and procedures, or caused such disclosure controls andprocedures 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)            Designed such internal control over financial reporting,or caused such internal control over financial reporting to be designed underour supervision, to provide reasonable assurance regarding the reliability offinancial reporting and the preparation of financial statements for externalpurposes in accordance with generally accepted accounting principles;

 

c)             Evaluated theeffectiveness of the registrant’s disclosure controls and procedures andpresented in this report our conclusions about the effectiveness of thedisclosure controls and procedures, as of the end of the period covered by thisreport based on such evaluation; and

 

d)            Disclosed in thisreport any change in the registrant’s internal control over financial reportingthat occurred during the registrant’s most recent fiscal quarter (theregistrant’s fourth fiscal quarter in the case of an annual report) that hasmaterially affected, or is reasonably likely to materially affect, theregistrant’s internal control over financial reporting; and

 

5.             The registrant’sother certifying 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 significantdeficiencies and material weaknesses in the design or operation of internalcontrol over financial reporting which are reasonably likely to adverselyaffect the registrant’s ability to record, process, summarize and reportfinancial information; and

 

b)            any fraud, whetheror not material, that involves management or other employees who have asignificant role in the registrant’s internal control over financial reporting.

 
| Date:   February 9, 2006 | Name:  | /s/Surendra Pai         |   |
|-----------------------------------------|--------|-------------------------|--------|
|                                    |   |                    |
|                                    | Title: | Chief Executive Officer |

 

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