**Exhibit 15**

**CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM**

 

We consent to the incorporation by reference in the following Registration Statements of Commtouch Software Ltd. on:

 

|   | (a) | Form S-8 NO. (333-94995) pertaining to the 1996 CSI Stock Option Plan, the 1999 Section 3(i) Share Option Plan and the 1999 Non-Employee Directors Stock Option Plan of Commtouch Software Ltd.; |
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|   | (b) | Form F-3 NO. (333-46192) pertaining to the registration by Commtouch Software Ltd. of 4,000,000 of its ordinary shares; |
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|   | (c) | Form S-8 NO. (333-65532) pertaining to the 1999 Non-Employee Directors Stock Option Plan; |
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|   | (d) | Form F-3 NO. (333-88248) pertaining to the registration by Commtouch Software Ltd. of 7,095,886 of its ordinary shares; |
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|   | (e) | Form F-3 NO. (333-109837) pertaining to the registration by Commtouch Software Ltd. of 8,793,564 of its ordinary shares; |
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|   | (f) | Form F-3 NO. (333-111731) pertaining to the registration by Commtouch Software Ltd. of 11,345,358 of its ordinary shares; |
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|   | (g) | Form F-3 NO. (333-111734) pertaining to the registration by Commtouch Software Ltd. of 4,162,479 of its ordinary shares; |
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|   | (h) | Form F-3 NO. (333-117085) pertaining to the registration by Commtouch Software Ltd. of 23,363,879 of its ordinary shares; |
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|   | (i) | Form F-3 NO. (333-121918) pertaining to the registration by Commtouch Software Ltd. of 6,955,684 of its ordinary shares; |
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|   | (j) | Form F-3 NO. (333-122407) pertaining to the registration by Commtouch Software Ltd. of 12,760,000 of its ordinary shares; |
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|   | (k) | Form F-3 NO. (333-131272) pertaining to the registration by Commtouch Software Ltd. of 9,000,000 of its ordinary shares; |
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of our report dated February 21, 2006, with respect to the consolidated financial statements of Commtouch Software Ltd. included in this Annual Report on Form 20-F for the year ended December 31,2005.

 

|  
/s/ KOST FORER GABBAY & KASIERER

Tel-Aviv, Israel

KOST FORER GABBAY & KASIERER

 
June 26, 2006

A Member of Ernst & Young Global

 
 

 

 

 

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