ASSIGNMENT, ASSUMPTION AND RECOGNITION AGREEMENT

Exhibit 99.15a


EXECUTION COPY


ASSIGNMENT, ASSUMPTION AND RECOGNITION AGREEMENT

THIS ASSIGNMENT, ASSUMPTION AND RECOGNITION AGREEMENT, dated May 1,
2006, ("Agreement") among Morgan Stanley Mortgage Capital Inc. ("Assignor"),
Morgan Stanley Capital I Inc. ("Assignee") and Wells Fargo Bank, National
Association (in such capacity, the "Company") and acknowledged by LaSalle Bank
National Association ("LaSalle"), as trustee ("Trustee") of Morgan Stanley
Mortgage Loan Trust 2006-7 (the "Trust"), and Wells Fargo Bank, National
Association, as master servicer (or any successor master servicer, the "Master
Servicer"):

For and in consideration of the sum of TEN DOLLARS ($10.00) and
other valuable consideration the receipt and sufficiency of which hereby are
acknowledged, and of the mutual covenants herein contained, the parties hereto
hereby agree as follows:

1. Assignment and Conveyance

The Assignor hereby conveys, sells, grants, transfers and assigns to the
Assignee all of the right, title and interest of the Assignor, as purchaser,
in, to and under (a) those certain mortgage loans listed on the schedule (the
"Mortgage Loan Schedule") attached hereto as Exhibit A (the "Mortgage Loans")
and (b) except as described below, that certain Master Seller's Warranties and
Servicing Agreement dated as of April 1, 2006 (the "SWSA"), between the
Assignor, as purchaser (the "Purchaser"), and the Company, as servicer, solely
insofar as the SWSA relates to the Mortgage Loans. In connection with the
transfer of the Mortgage Loans hereunder, the Company agrees that, from and
after the date hereof, each Mortgage Loan transferred hereunder will be
subject to, and serviced under, the SWSA.

The Assignor specifically reserves and does not assign to the
Assignee hereunder any and all right, title and interest in, to and under and
any obligations of the Assignor with respect to any mortgage loans subject to
the SWSA which are not the Mortgage Loans set forth on the Mortgage Loan
Schedule and are not the subject of this Agreement.

2. Recognition of the Company

From and after the date hereof (the "Closing Date"), the Company shall
and does hereby recognize that the Assignor will transfer the Mortgage Loans
and assign its rights under the SWSA to the Assignee and that the Assignee
will thereafter transfer the Mortgage Loans and assign its rights under the
SWSA and this Agreement to the Trust created pursuant to a pooling and
servicing agreement, dated as of May 1, 2006 (the "Pooling Agreement"), among
the Assignee, Wells Fargo Bank, National Association, as securities
administrator, the Master Servicer and the Trustee. The Company hereby
acknowledges and agrees that from and after the date hereof (i) the Trust will
be the owner of the Mortgage Loans, (ii) the Company shall look solely to the
Trust for performance of any obligations of the Assignor insofar as they
relate to the enforcement of the representations, warranties and covenants
with respect to the Mortgage Loans, (iii) the Trust (including the Trustee
and, with respect to the servicing of the Mortgage Loans, the Master Servicer
acting on the Trust's behalf) shall have all the rights and remedies available
to the Assignor, insofar as they relate to the Mortgage Loans, under the SWSA,
including, without limitation, the enforcement of the document delivery
requirements set forth in Section 2.01 of the SWSA, and shall be entitled to
enforce all of the obligations of the Company thereunder insofar as they
relate to the Mortgage Loans, and (iv) all references to the Owner (insofar as
they relate to the rights, title and interest and, with respect to obligations
of the Owner, only insofar as they relate to the enforcement of the
representations, warranties and covenants of the Company) under the SWSA
insofar as they relate to the Mortgage Loans, shall be deemed to refer to the
Trust. Neither the Company nor the Assignor shall amend or agree to amend,
modify, waive, or otherwise alter any of the terms or provisions of the SWSA
which amendment, modification, waiver or other alteration would in any way
affect the Mortgage Loans

<PAGE>

or the Company's performance under the SWSA with respect to the Mortgage Loans
without the prior written consent of the Trustee and the Master Servicer.

3. Notwithstanding any statement to the contrary in Section 2 above, the
Company shall and does hereby acknowledge that the indemnification provisions
set forth in Section 3.03, Section 8.01 and the first instance of Section
9.01(f) of the SWSA shall be available to and for the benefit of the Assignor,
the Assignee and the Trust (including the Trustee and the Master Servicer
acting on the Trust's behalf), as provided in the SWSA.

4. Representations and Warranties

a. The Assignee represents and warrants that it is a sophisticated
investor able to evaluate the risks and merits of the transactions
contemplated hereby, and that it has not relied in connection therewith
upon any statements or representations of the Assignor or the Company
other than those contained in the SWSA or this Agreement.

b. Each of the parties hereto represents and warrants that it is
duly and legally authorized to enter into this Agreement.

c. Each of the Assignor, Assignee and Company hereto represents and
warrants that this Agreement has been duly authorized, executed and
delivered by it and (assuming due authorization, execution and delivery
thereof by each of the other parties hereto) constitutes its legal, valid
and binding obligation, enforceable against it in accordance with its
terms, except as such enforcement may be limited by bankruptcy,
insolvency, reorganization or other similar laws affecting the
enforcement of creditors' rights generally and with respect to the
Company, similar laws administered by the FDIC affecting the contract
obligations of insured banks and by general equitable principles
(regardless of whether such enforcement is considered in a proceeding in
equity or at law).

d. The Company hereby restates, as of the Closing Date (as defined
in the Pooling Agreement, the representations and warranties set forth in
Section 3.01 of the SWSA to and for the benefit of the Assignee and the
Trust, and by this reference incorporates such representations and
warranties herein, as of such Closing Date.

5. The Company hereby acknowledges that Wells Fargo Bank, National Association
has been appointed as the Master Servicer of the Mortgage Loans pursuant to
the Pooling Agreement and, therefore, has the right to enforce all obligations
of the Company under the SWSA. Such rights will include, without limitation,
the right to terminate the Company under the SWSA upon the occurrence of an
event of default thereunder, the right to receive all remittances required to
be made by the Company under the SWSA, the right to receive all monthly
reports and other data required to be delivered by the Company under the SWSA,
the right to examine the books and records of the Company, indemnification
rights and the right to exercise certain rights of consent and approval
relating to actions taken by the Assignor. The Company shall make all
distributions under the SWSA to the Master Servicer by wire transfer of
immediately available funds to:

Wells Fargo Bank, National Association
ABA Number: 121-000-248
Account Name: Corporate Trust Clearing
Account number: 3970771416
For further credit to: 50922400, MSM 2006-7

<PAGE>


The Company shall deliver all reports required to be delivered under
this Agreement to the Master Servicer at the following address:

Wells Fargo Bank, National Association
9062 Old Annapolis Road
Columbia, Maryland 21045
Attention: Client Manager, MSM 2006-7
Telecopier: (410) 715-2380

6. Certain Matters Regarding the Trustee

Each party hereto hereby agrees as follows:

It is expressly understood and agreed by the parties hereto that (i) this
Assignment is executed and delivered by LaSalle Bank National Association, not
individually or personally but solely on behalf of the Trust, as the assignee,
in the exercise of the powers and authority conferred and vested in it, as
Trustee, pursuant to the Pooling Agreement, (ii) each of the representations,
undertakings and agreements herein made on the part of assignee is made and
intended not as personal representations, undertakings and agreements by
LaSalle Bank National Association but is made and intended for the purpose of
binding only the Trust, (iii) nothing herein contained shall be construed as
creating any liability for LaSalle Bank National Association, individually or
personally, to perform any covenant (either express or implied) contained
herein, (iv) under no circumstances shall LaSalle Bank National Association be
personally liable for the payment of any indebtedness or expenses of the
Trust, or be liable for the breach or failure of any obligation,
representation, warranty or covenant made or undertaken by the Trust under
this Assignment and (v) all recourse for any payment liability or other
obligation of the assignee shall be had solely to the assets of the Trust.

7. Amendments to the SWSA

The parties to this Agreement hereby agree to amend the SWSA as follows:

a. With respect to Article I, "Permitted Investments" shall have
the meaning of such term as defined in the Pooling and
Servicing Agreement.

b. With respect to Article I, the definition of "Static Pool
Information" shall be inapplicable.

c. With respect to Article I, the definition of "Third-Party
Originator" shall be inapplicable.

d. Section 3.01(i) (Selection Process), Section 3.01(k) (Sale
Treatment) and Section 3.01(m) (No Broker's Fees) of the SWSA
shall be inapplicable.

e. Section 3.02 shall be inapplicable.

f. Section 4.05(vii) is hereby amended to add the term "Monthly
Advances," prior to the term "Servicing Advances."

g. The following is added as the second paragraph of Section 4.09:

<PAGE>

"Amounts on deposit in the Custodial Account may at the
option of the Servicer be invested in Permitted
Investments. Any such Permitted Investment shall be made
in the name of the Servicer in trust for the benefit of
the Owner. All income on or gain realized from any such
Permitted Investment shall be for the benefit of the
Servicer and may be withdrawn from the Custodial Account
at any time by the Servicer. Any losses incurred in
respect of any such investment shall be deposited in the
Custodial Account, by the Servicer out of its own funds
immediately as realized."

h. The words "on or before the Remittance Date" are hereby deleted
from the first sentence of Section 4.17.

i. The second sentence of the second paragraph of Section 5.01 is
hereby amended and restated in its entirety as follows:

"Such interest shall be deposited in the Custodial Account
by the Company on the date such late payment is made and
shall cover the period commencing with the day following
the Business Day on which such payment was due and ending
with the Business Day on which such payment is made, both
inclusive."

j. The first paragraph of Section 5.02 is hereby amended and
restated in its entirety as follows:

"Not later than the Remittance Report Date, the Company
shall furnish to the Purchaser in an electronic form the
information required by the reports attached hereto as
Exhibit II, or a form otherwise mutually agreed to by the
Company and Purchaser, with a trial balance report
attached thereto, as to the remittance period ending on
the last day of the preceding month."

k. Section 6.05 is hereby deleted in its entirety.

l. The third clause of the first sentence of Section 6.07(ii) is
hereby amended and restated as follows:

"which continues unremedied for fourteen (14) calendar
days after the date on which such information,"

m. Section 9.01(e)(i) is hereby deleted in its entirety.

n. Section 9.01(e)(ii) is hereby deleted in its entirety.

o. Section 9.01(e)(iii) is amended to require the Company to
comply with the obligations thereof in connection with the
purchase of servicing rights for the Specified Mortgage Loans.

p. The following is added as the second paragraph of Section
9.01(e)(vii):

<PAGE>

"The Company shall provide to the Purchaser, any Master
Servicer and any Depositor, evidence of the authorization
of the person signing any certification or statement,
copies or other evidence of Fidelity Bond Insurance and
Errors and Omission Insurance policy, financial
information and reports, and such other information
related to the Company or any Subservicer or the Company
or such Subservicer's performance hereunder."

q. Section 9.01(f)(i)(A) is amended to change the cross-reference
regarding material provided in written or electronic form from
"Section 9.01(f)" to "Section 9.01(e)".

r. Section 10.01(ii) is hereby amended and restated in its
entirety as follows:

"failure by the Company duly to observe or perform in any
material respect any other of the covenants or agreements
on the part of the Company set forth in this Agreement
(other than as set forth in Section 6.07) which continues
unremedied for a period of 90 days after the date on which
written notice of such failure, requiring the same to be
remedied, shall have been given to the Company by the
Purchaser or by the Custodian; or"

s. Written notice provided in compliance with Sections 9.01
(e)(iv), (v) and (vi) of the SWSA shall be substantially in the
form of Exhibit III to this Agreement.

8. Miscellaneous

A copy of all assessments, attestations, reports and certifications
required to be delivered by the Servicer under this Agreement and the SWSA
shall be delivered to the Master Servicer by the date(s) specified herein or
therein, and where such documents are required to be addressed to any party,
such addressees shall include the Master Servicer and the Master Servicer
shall be entitled to rely on such documents.

Any notices or other communications permitted or required under the
Agreement to be made to the Assignor, Assignee, the Master Servicer, the
Company, and the Trustee shall be made in accordance with the terms of the
Agreement and shall be sent to the Depositor and Trustee as follows:

In the case of the Depositor:

Morgan Stanley Capital I Inc.
1585 Broadway
New York, New York 10036
Attention: Morgan Stanley Mortgage Loan Trust 2006-7

In the case of the Trustee:

LaSalle Bank National Association
135 South LaSalle Street, Suite 1625
Chicago, Illinois 60603
Attention: Global Securities and Trust Services MSM 2006-7

In the case of the Company:

Wells Fargo Bank, N.A.

<PAGE>

1 Home Campus
Des Moines, Iowa 50328-0001
Attention: John B. Brown, MAC#X2401-042

With a copy to

Wells Fargo Bank, N.A.
7485 New Horizon Way
Frederick, Maryland 21703
Attention: Laurie McGoogan, MAC#X3901-01C

With a copy to:

Wells Fargo Bank, N.A.
1 Home Campus
Des Moines, Iowa 50328-0001
Attention: General Counsel, MAC#X2401-06T

9. This Agreement shall be construed in accordance with the laws of
the State of New York, without regard to conflicts of law principles, and the
obligations, rights and remedies of the parties hereunder shall be determined
in accordance with such laws.

10. No term or provision of this Agreement may be waived or modified
unless such waiver or modification is in writing and signed by the party
against whom such waiver or modification is sought to be enforced.

11. This Agreement shall inure to the benefit of (i) the successors
and assigns of the parties hereto and (ii) the Trust (including the Trustee
and the Master Servicer acting on the Trust's behalf). Any entity into which
Assignor, Assignee or Company may be merged or consolidated shall, without the
requirement for any further writing, be deemed Assignor, Assignee or Company,
respectively, hereunder.

12. Each of this Agreement and the SWSA shall survive the conveyance
of the Mortgage Loans and the assignment of the SWSA (solely with respect to
the Mortgage Loans) by Assignor to Assignee and nothing contained herein shall
supersede or amend the terms of the SWSA.

13. This Agreement may be executed simultaneously in any number of
counterparts. Each counterpart shall be deemed to be an original and all such
counterparts shall constitute one and the same instrument.

14. In the event that any provision of this Agreement conflicts with
any provision of the SWSA with respect to the Mortgage Loans, the terms of
this Agreement shall control.

15. Capitalized terms used in this Agreement (including the exhibits
hereto) but not defined in this Agreement shall have the meanings given to
such terms in the SWSA.

[SIGNATURE PAGE FOLLOWS]

<PAGE>

IN WITNESS WHEREOF, the parties have caused this Agreement to be executed
by their duly authorized officers as of the date first above written.

MORGAN STANLEY MORTGAGE CAPITAL INC.

By: /s/ Valerie Kay
-----------------------------
Name: Valerie Kay
Title: Vice President

MORGAN STANLEY CAPITAL I INC.

By: /s/ Valerie Kay
-----------------------------
Name: Valerie Kay
Title: Vice President


WELLS FARGO BANK, N.A.

By: /s/ Laurie McGoogan
-----------------------------
Name: Laurie McGoogan
Title: Vice President


Acknowledged and Agreed:
WELLS FARGO BANK, NATIONAL
ASSOCIATION, as Master Servicer

By: /s/ Patricia M. Russo
-----------------------------------
Name: Patricia M. Russo
Title: Vice President

LASALLE BANK NATIONAL ASSOCIATION,
as Trustee of Morgan Stanley
Mortgage Loan Trust 2006-7

By: /s/ Christopher Lewis
-----------------------------------
Name: Christopher Lewis
Title: Assistant Vice President

<PAGE>

Schedule I

Specified Mortgage Loan Schedule

[see Schedule A to the Pooling and Servicing Agreement
on file with the Servicer, the Master Servicer and the Depositor]

<PAGE>

Execution Copy

Exhibit IIA: Standard File Layout - Delinquency Reporting

<TABLE>
<CAPTION>
--------------------------------------------------------------------------------------------------------------------------------
Column/Header Name Description Decimal Format
Comment
--------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C>
SERVICER_LOAN_NBR A unique number assigned to a loan by the Servicer. This
may be different than the LOAN_NBR
--------------------------------------------------------------------------------------------------------------------------------
LOAN_NBR A unique identifier assigned to each loan by the originator.
--------------------------------------------------------------------------------------------------------------------------------
CLIENT_NBR Servicer Client Number
--------------------------------------------------------------------------------------------------------------------------------
SERV_INVESTOR_NBR Contains a unique number as assigned by an external servicer
to identify a group of loans in their system.
--------------------------------------------------------------------------------------------------------------------------------
BORROWER_FIRST_NAME First Name of the Borrower.
--------------------------------------------------------------------------------------------------------------------------------
BORROWER_LAST_NAME Last name of the borrower.
--------------------------------------------------------------------------------------------------------------------------------
PROP_ADDRESS Street Name and Number of Property
--------------------------------------------------------------------------------------------------------------------------------
PROP_STATE The state where the property located.
--------------------------------------------------------------------------------------------------------------------------------
PROP_ZIP Zip code where the property is located.
--------------------------------------------------------------------------------------------------------------------------------
BORR_NEXT_PAY_DUE_DATE The date that the borrower's next payment is due to the MM/DD/YYYY
servicer at the end of processing cycle, as reported by
Servicer.
--------------------------------------------------------------------------------------------------------------------------------
LOAN_TYPE Loan Type (i.e. FHA, VA, Conv)
--------------------------------------------------------------------------------------------------------------------------------
BANKRUPTCY_FILED_DATE The date a particular bankruptcy claim was filed. MM/DD/YYYY
--------------------------------------------------------------------------------------------------------------------------------
BANKRUPTCY_CHAPTER_CODE The chapter under which the bankruptcy was filed.
--------------------------------------------------------------------------------------------------------------------------------
BANKRUPTCY_CASE_NBR The case number assigned by the court to the bankruptcy
filing.
--------------------------------------------------------------------------------------------------------------------------------
POST_PETITION_DUE_DATE The payment due date once the bankruptcy has been approved MM/DD/YYYY
by the courts
--------------------------------------------------------------------------------------------------------------------------------
BANKRUPTCY_DCHRG_DISM_DATE The Date The Loan Is Removed From Bankruptcy. Either by MM/DD/YYYY
Dismissal, Discharged and/or a Motion For Relief Was
Granted.
--------------------------------------------------------------------------------------------------------------------------------
LOSS_MIT_APPR_DATE The Date The Loss Mitigation Was Approved By The Servicer MM/DD/YYYY
--------------------------------------------------------------------------------------------------------------------------------
LOSS_MIT_TYPE The Type Of Loss Mitigation Approved For A Loan Such As;
--------------------------------------------------------------------------------------------------------------------------------
LOSS_MIT_EST_COMP_DATE The Date The Loss Mitigation /Plan Is Scheduled To End/Close MM/DD/YYYY
--------------------------------------------------------------------------------------------------------------------------------
LOSS_MIT_ACT_COMP_DATE The Date The Loss Mitigation Is Actually Completed MM/DD/YYYY
--------------------------------------------------------------------------------------------------------------------------------
FRCLSR_APPROVED_DATE The date DA Admin sends a letter to the servicer with MM/DD/YYYY
instructions to begin foreclosure proceedings.
--------------------------------------------------------------------------------------------------------------------------------
ATTORNEY_REFERRAL_DATE Date File Was Referred To Attorney to Pursue Foreclosure MM/DD/YYYY
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