UNITED STATES
                             SECURITIES AND EXCHANGE COMMISSION
                                   WASHINGTON, D.C. 20549



                                          FORM 10-K/A
                                        Amendment No. 1

The Issuing Entity is filing this Form 10-K/A to replace Exhibits 31, 33(a)
and 34(a) to the original Form 10-K filed on March 30, 2007. American Security
Insurance Company, Standard Guaranty Insurance Company and TrackSure Insurance
Agency, Inc. (formerly, "Safeco Financial Institution Solutions, Inc.")
("Assurant Inc.") recently provided the Issuing Entity with a revised report on
assessment of compliance with servicing criteria for asset-backed securities
and a related attestation. In the original assessment previously provided to
the Issuing Entity, Assurant Inc. excluded Item 1122(d)(4)(xii) from the scope
of its assessment. Assurant Inc. recently provided the Issuing Entity with a
revised assessment of compliance that assesses Assurant Inc.'s compliance with
Item 1122(d)(4)(xii) and identifies material instance of non compliance with
this criterion. This material instance of non compliance is noted in this Form
10-K/A under "Additional Disclosure Items For Regulation AB." The Issuing
Entity has included this revised assessment of compliance under Exhibit 33(a),
the related attestation under Exhibit 34(a) and a revised Rule
13a-14(d)/15d-14(d) Certification under Exhibit 31. This Form 10-K/A does not
otherwise amend the original Form 10-K filed with the Commission on
March 30, 2007.


  (Mark one)

  /X/ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
      EXCHANGE ACT OF 1934
      For the fiscal year ended December 31, 2006

      OR



  / / TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
      EXCHANGE ACT OF 1934


       Commission file number:  333-127872-07

       CSMC Mortgage-Backed Trust Series 2006-1
       (exact name of issuing entity as specified in its charter)

       Credit Suisse First Boston Mortgage Securities Corp.
       (exact name of the depositor as specified in its charter)

       DLJ Mortgage Capital, Inc.
       (exact name of the sponsor as specified in its charter)


  New York                                          54-2193476
  (State or other jurisdiction of                   54-2193477
  incorporation or organization)                    54-2193478
                                                    54-2193479
                                                    54-2193480
                                                    (I.R.S. Employer
                                                    Identification No.)


   c/o Wells Fargo Bank, N.A.
   9062 Old Annapolis Rd.
   Columbia, MD                                21045
  (Address of principal executive offices)    (Zip Code)


  Registrant's telephone number, including area code: (410) 884-2000


  Securities registered pursuant to Section 12(b) of the Act:

        NONE.


  Securities registered pursuant to Section 12(g) of the Act:

        NONE.


  Indicate by check mark if the registrant is a well-known seasoned issuer,
  as defined in Rule 405 of the Securities Act.

        Yes  ___     No  X


  Indicate by check mark if the registrant is not required to file reports
  pursuant to Section 13 or Section 15(d) of the Act.

        Yes  ___     No  X


  Indicate by check mark whether the registrant (1) has filed all reports
  required to be filed by Section 13 or 15(d) of the Securities Exchange
  Act of 1934 during the preceding 12 months (or for such shorter period
  that the registrant was required to file such reports), and (2) has been
  subject to such filing requirements for the past 90 days.

        Yes  X       No  ___


  Indicate by check mark if disclosure of delinquent filers pursuant to
  Item 405 of Regulation S-K ( 229.405 of this chapter) is not contained
  herein, and will not be contained, to the best of registrant's knowledge,
  in definitive proxy or information statements incorporated by reference
  in Part III of this Form 10-K or any amendment to this Form 10-K.

        Not applicable.


  Indicate by check mark whether the registrant is a large accelerated filer,
  an accelerated filer, or a non-accelerated filer. See definition of
  "accelerated filer and large accelerated filer" in Rule 12b-2 of the
  Exchange Act. (Check one):


  Large accelerated filer ___  Accelerated filer ___  Non-accelerated filer X


  Indicate by check mark whether the registrant is a shell company (as
  defined in Rule 12b-2 of the Act).

        Yes  ___     No  X


  State the aggregate market value of the voting and non-voting common
  equity held by non-affiliates computed by reference to the price at which
  the common equity was last sold, or the average bid and asked price of
  such common equity, as of the last business day of the registrant's most
  recently completed second fiscal quarter.

        Not applicable.


     Documents Incorporated by Reference

  List hereunder the following documents if incorporated by reference and
  the Part of the Form 10-K (e.g., Part I, Part II, etc.) into which the
  document is incorporated: (1)Any annual report to security holders; (2)
  Any proxy or information statement; and (3)Any prospectus filed pursuant
  to Rule 424(b) or (c) under the Securities Act of 1933. The listed
  documents should be clearly described for identification purposes (e.g.,
  annual report to security holders for fiscal year ended December 24, 1980).

        Not applicable.


                                   PART I
  Item 1.  Business.

            Omitted.


  Item 1A.  Risk Factors.

            Omitted.


  Item 1B.  Unresolved Staff Comments.

            None.


  Item 2.  Properties.

            Omitted.


  Item 3.  Legal Proceedings.

            Omitted.


  Item 4.  Submission of Matters to a Vote of Security Holders.

            Omitted.


                                PART II

  Item 5. Market for Registrants Common Equity, Related Stockholder
          Matters and Issuer Purchases of Equity Securities.

            Omitted.


  Item 6.  Selected Financial Data.

            Omitted.


  Item 7.  Management's Discussion and Analysis of Financial Condition and
           Results of Operations.

            Omitted.


  Item 7A. Quantitative and Qualitative Disclosures About Market Risk.

            Omitted.


  Item 8.  Financial Statements and Supplementary Data.

            Omitted.


  Item 9.  Changes in and Disagreements With Accountants on Accounting and
           Financial Disclosure.

            Omitted.


  Item 9A. Controls and Procedures.

            Omitted.


  Item 9A(T). Controls and Procedures.

            Omitted.


  Item 9B. Other Information.

            None.


                                PART III

  Item 10. Directors, Executive Officers and Corporate Governance.

            Omitted.


  Item 11. Executive Compensation.

            Omitted.

  Item 12. Security Ownership of Certain Beneficial Owners and
           Management and Related Stockholder Matters.

            Omitted.


  Item 13. Certain Relationships and Related Transactions, and Director
           Independence.

            Omitted.


  Item 14. Principal Accounting Fees and Services.

            Omitted.



                ADDITIONAL DISCLOSURE ITEMS FOR REGULATION AB

  Item 1112(b) of Regulation AB, Significant Obligor Financial Information.

            No single obligor represents more than 10% of the pool assets held
            by this transaction.


  Item 1114(b)(2) and 1115(b) of Regulation AB, Significant Enhancement
             Provider Financial Information.



            No entity or group of affiliated entities provides any external
            credit enhancement, uses any derivative instruments or other support
            for the certificates within this transaction.



  Item 1117 of Regulation AB, Legal Proceedings.

            The registrant knows of no material pending legal proceedings
            involving the entities contemplated by Item 1117 of Regulation AB,
            other than routine litigation incidental to the duties of those
            respective parties.



  Item 1119 of Regulation AB, Affiliations and Certain Relationships and
             Related Transactions.


            None.

  Item 1122 of Regulation AB, Compliance with Applicable Servicing Criteria.


            The servicing criteria have been completed within the manner stated
            in the governing documents and are attached hereto under Item 15.

            Assurant, Inc. previously excluded the applicable servicing
            criteria set forth in Item 1122 (d)(4)(xii) from the scope of its
            assessment of compliance. Assurant, Inc. has now assessed its
            compliance with the Applicable Servicing Criteria for the Reporting
            Period of January 1, 2006 through December 31, 2006 and has
            identified a material instance of noncompliance with that servicing
            criterion. Specifically, Assurant, Inc. did not have, during the
            Reporting Period, sufficient policies and procedures to capture the
            information with respect to the Platform Transactions necessary to
            determine compliance with Item 1122(d)(4)(xii). Accordingly,
            Assurant, Inc. has restated its previous assessment for the
            Reporting Period, which excluded evaluation of the criterion,
            to include the criterion and reflect the material noncompliance as
            a result of its assessment.

           The 1122 statements for First American Real Estate Solutions of
           Texas, L.P. (as Sub-Contractor for Fifth Third Mortgage Company )
           has disclosed the following material instance of noncompliance with
           the servicing criteria set forth in Item 1122(d)(2)(vii)(B) of
           Regulation AB applicable to the Company during year ended December
           31, 2006. Account reconciliations for all asset-backed securities
           related bank accounts were not prepared within 30 calendar days
           after the bank statement cutoff date, or such other number of
           days specified in the transaction agreements as required by Item
           1122(d)(2)(vii)(B) of Regulation AB.



            The 1122 statements for Wells Fargo Bank, N.A. (servicer) has
            disclosed the following instances of material noncompliance with
            certain servicing criteria applicable to the Company during the year
            ended December 31, 2006:

            1. 1122(d)(3)(i) - Delinquency Reporting - The Company provided
               incomplete data to some third parties who use such data to
               calculate delinquency ratios and determine the status of loans
               with respect to bankruptcy, foreclosure or real estate owned.
               Instead of the actual due date being provided for use in
               calculating delinquencies, the date of the first payment due to
               the security was provided.

            2. 1122(d)(4)(vii) - Notification of Intent to Foreclose - The
               Company, as required by certain servicing agreements, did not
               provide investors with prior notification of intent to foreclose.



            The 1122 statements for Wells Fargo Bank, National Association
            (Corporate Trust Services) has disclosed material noncompliance with
            criterion 1122(d)(3)(i), as applicable to the Company during the
            twelve months ended December 31, 2006.  Certain monthly investor or
            remittance reports included errors in the calculation and/or the
            reporting of delinquencies for the pool assets.






  Item 1123 of Regulation AB, Servicer Compliance Statement.


            The servicer compliance statements have been completed within the
            manner stated in the governing documents and are attached hereto
            under Item 15.





                                PART IV


  Item 15. Exhibits, Financial Statement Schedules.

   (a) Exhibits


     (4) POOLING AND SERVICING AGREEMENT, dated as of January 1, 2006,
         among CREDIT SUISSE FIRST BOSTON MORTGAGE SECURITIES  CORP., a Delaware
         corporation, as depositor (the "Depositor"), DLJ MORTGAGE CAPITAL, INC.
         ("DLJMC"), a Delaware corporation, as seller ("Seller"), as a servicer
         (a "Servicer"), WELLS FARGO BANK, N.A. ("Wells Fargo"), a national
         banking association, in its capacity as a servicer (a "Servicer"), as
         master servicer (the "Master Servicer") and as trust administrator
         (the "Trust Administrator"), WASHINGTON MUTUAL MORTGAGE SECURITIES
         CORP. ("WMMSC"), a Delaware corporation, as a servicer (a "Servicer"),
         GREENPOINT MORTGAGE FUNDING, INC., a New York corporation
         ("GreenPoint"), as a seller (in such capacity, a "Seller"), and as
         a servicer (in such capacity, a "Servicer"),  SELECT PORTFOLIO
         SERVICING, INC. ("SPS"), a Utah corporation, in its capacity as a
         servicer (a "Servicer") and in its capacity as a special servicer (the
         "Special Servicer"),  and U.S. BANK NATIONAL ASSOCIATION, a national
         banking association, as trustee (the "Trustee").  (incorporated herein
         by reference from Exhibit 99 of the Current  Report on Form 8-K of the
         Issuing Entity, as filed with the Commission on February 14, 2006).

     (10) Incorporated by reference as Exhibit (4).



     (31) Rule 13a-14(d)/15d-14(d) Certifications.

    (33) Reports on assessment of compliance with servicing criteria for
         asset-backed securities.

      <TABLE>

      
         <c>
      a) Assurant Inc. as Sub-Contractor for Fifth Third Mortgage Company <F1>
      b) Fifth Third Mortgage Company, as Servicer <F1>
      c) First American Real Estate Solutions of Texas, L.P. as Sub-Contractor for Fifth Third Mortgage Company <F1>
      d) LaSalle Bank, National Association, as Custodian <F1>
      e) Regulus Group LLC as Sub-Contractor for Wells Fargo Bank, N.A. <F1>
      f) Select Portfolio Servicing, Inc., as Servicer <F1>
      g) Wells Fargo Bank, N.A., as Servicer <F1>
      h) Wells Fargo Bank, N.A., as Master Servicer <F1>
      i) Wells Fargo Bank, N.A., as Trust Administrator <F1>
      j) Wells Fargo Bank, N.A., as Custodian <F1>
      k) ZC Sterling Insurance Agency, Inc. as Sub-Contractor for Wells Fargo Bank, N.A. <F1>

      </TABLE>

     (34) Attestation reports on assessment of compliance with servicing
          criteria for asset-backed securities.

      <TABLE>

      
        <c>
      a) Assurant Inc. as Sub-Contractor for Fifth Third Mortgage Company <F1>
      b) Fifth Third Mortgage Company, as Servicer <F1>
      c) First American Real Estate Solutions of Texas, L.P. as Sub-Contractor for Fifth Third Mortgage Company <F1>
      d) LaSalle Bank, National Association, as Custodian <F1>
      e) Regulus Group LLC as Sub-Contractor for Wells Fargo Bank, N.A. <F1>
      f) Select Portfolio Servicing, Inc., as Servicer <F1>
      g) Wells Fargo Bank, N.A., as Servicer <F1>
      h) Wells Fargo Bank, N.A., as Master Servicer <F1>
      i) Wells Fargo Bank, N.A., as Trust Administrator <F1>
      j) Wells Fargo Bank, N.A., as Custodian <F1>
      k) ZC Sterling Insurance Agency, Inc. as Sub-Contractor for Wells Fargo Bank, N.A. <F1>

      </TABLE>

     (35) Servicer compliance statement.

      <TABLE>

      
         <c>
      a) Select Portfolio Servicing, Inc., as Servicer <F1>
      b) Wells Fargo Bank, N.A., as Servicer <F1>
      c) Wells Fargo Bank, N.A., as Master Servicer <F1>
      d) Wells Fargo Bank, N.A., as Trust Administrator <F1>

      </TABLE>

   (b) Not applicable.

   (c) Omitted.


  <F1> Filed herewith.



                                SIGNATURES

  Pursuant to the requirements of Section 13 or 15(d) of the Securities
  Exchange Act of 1934, the registrant has duly caused this report to be
  signed on its behalf by the undersigned, thereunto duly authorized.



    Credit Suisse First Boston Mortgage Securities Corp.
    (Depositor)



    /s/ Bruce Kaiserman
    Bruce Kaiserman, Vice President
    (senior officer in charge of securitization of the depositor)

    Date: May 23, 2008


  Exhibit Index

  Exhibit No.


     (4) POOLING AND SERVICING AGREEMENT, dated as of January 1, 2006,
         among CREDIT SUISSE FIRST BOSTON MORTGAGE SECURITIES  CORP., a Delaware
         corporation, as depositor (the "Depositor"), DLJ MORTGAGE CAPITAL, INC.
         ("DLJMC"), a Delaware corporation, as seller ("Seller"), as a servicer
         (a "Servicer"), WELLS FARGO BANK, N.A. ("Wells Fargo"), a national
         banking association, in its capacity as a servicer (a "Servicer"), as
         master servicer (the "Master Servicer") and as trust administrator
         (the "Trust Administrator"), WASHINGTON MUTUAL MORTGAGE SECURITIES
         CORP. ("WMMSC"), a Delaware corporation, as a servicer (a "Servicer"),
         GREENPOINT MORTGAGE FUNDING, INC., a New York corporation
         ("GreenPoint"), as a seller (in such capacity, a "Seller"), and as
         a servicer (in such capacity, a "Servicer"),  SELECT PORTFOLIO
         SERVICING, INC. ("SPS"), a Utah corporation, in its capacity as a
         servicer (a "Servicer") and in its capacity as a special servicer (the
         "Special Servicer"),  and U.S. BANK NATIONAL ASSOCIATION, a national
         banking association, as trustee (the "Trustee").  (incorporated herein
         by reference from Exhibit 99 of the Current  Report on Form 8-K of the
         Issuing Entity, as filed with the Commission on February 14, 2006).

     (10) Incorporated by reference as Exhibit (4).


     (31) Rule 13a-14(d)/15d-14(d) Certifications.

    (33) Reports on assessment of compliance with servicing criteria for
         asset-backed securities.

      <TABLE>

      
         <c>
      a) Assurant Inc. as Sub-Contractor for Fifth Third Mortgage Company
      b) Fifth Third Mortgage Company, as Servicer
      c) First American Real Estate Solutions of Texas, L.P. as Sub-Contractor for Fifth Third Mortgage Company
      d) LaSalle Bank, National Association, as Custodian
      e) Regulus Group LLC as Sub-Contractor for Wells Fargo Bank, N.A.
      f) Select Portfolio Servicing, Inc., as Servicer
      g) Wells Fargo Bank, N.A., as Servicer
      h) Wells Fargo Bank, N.A., as Master Servicer
      i) Wells Fargo Bank, N.A., as Trust Administrator
      j) Wells Fargo Bank, N.A., as Custodian
      k) ZC Sterling Insurance Agency, Inc. as Sub-Contractor for Wells Fargo Bank, N.A.

      </TABLE>

     (34) Attestation reports on assessment of compliance with servicing
          criteria for asset-backed securities.

      <TABLE>

      
        <c>
      a) Assurant Inc. as Sub-Contractor for Fifth Third Mortgage Company
      b) Fifth Third Mortgage Company, as Servicer
      c) First American Real Estate Solutions of Texas, L.P. as Sub-Contractor for Fifth Third Mortgage Company
      d) LaSalle Bank, National Association, as Custodian
      e) Regulus Group LLC as Sub-Contractor for Wells Fargo Bank, N.A.
      f) Select Portfolio Servicing, Inc., as Servicer
      g) Wells Fargo Bank, N.A., as Servicer
      h) Wells Fargo Bank, N.A., as Master Servicer
      i) Wells Fargo Bank, N.A., as Trust Administrator
      j) Wells Fargo Bank, N.A., as Custodian
      k) ZC Sterling Insurance Agency, Inc. as Sub-Contractor for Wells Fargo Bank, N.A.

      </TABLE>

     (35) Servicer compliance statement.

      <TABLE>

      
         <c>
      a) Select Portfolio Servicing, Inc., as Servicer
      b) Wells Fargo Bank, N.A., as Servicer
      c) Wells Fargo Bank, N.A., as Master Servicer
      d) Wells Fargo Bank, N.A., as Trust Administrator

      </TABLE>