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                                                                   EXHIBIT 10.57

                           [SILICON VALLEY BANK LOGO]

As of June 25, 2002

MTI Technology Corporation
4905 E. La Palma Avenue
Anaheim, CA 92807

Gentlemen:

     Reference is made to that certain Loan and Security Agreement, dated as of
October 29, 2001 (as amended, restated, supplemented, or otherwise modified from
time to time, the "Loan Agreement"), between MTI Technology Corporation
("Borrower") and Silicon Valley Bank ("Silicon"). Capitalized terms used but not
defined in this letter agreement shall have the meanings set forth in the Loan
Agreement.

          This letter agreement confirms that, subject to the following
provisions:

          (A) Borrower and Silicon have agreed to terminate the Loan Agreement
as of the date of this letter agreement;

          (B) Silicon has agreed to waive the termination fee set forth in
Section 6.2 of the Loan Agreement in connection with such termination; and

          (C) all Obligations have been paid or satisfied or cash-secured in
full;

provided, however; that: (1) all Obligations in respect of the Warrant and
related registration rights agreement shall remain in full force and effect and
survive such termination; (2) all Obligations to indemnify Silicon under the
Loan Agreement or any other related document and to reimburse Silicon for any
remaining costs and expenses shall remain in full force and effect and so
survive such termination; (3) Sections 9.15, 9.17, and 9.18 of the Loan
Agreement, and all other provisions of the Loan Agreement or any related
document that by their express terms survive any termination, shall remain in
full force and effect and so survive such termination; (4) to the extent that
any payments or proceeds (or any portion thereof) received by Silicon shall be
subsequently invalidated, declared to be fraudulent or a fraudulent conveyance
or preferential, set aside or required to be repaid to a trustee, receiver,
debtor-in-possession or any other party under any bankruptcy law, state or
federal law, common law or equitable cause, then to the extent that the payment
or proceeds is rescinded or must otherwise be restored by Silicon, whether as a
result of any proceedings in bankruptcy or reorganization or otherwise, the
Obligations or part thereof under or in respect of the Loan Agreement or related
document which were intended to be satisfied shall be revived and continue to be
in full force and effect, as if the payment or proceeds had never been received
by Silicon, and this letter agreement shall in no way impair the claims of
Silicon with respect to the revived Obligations under or in respect of the Loan
Agreement or related document; and (5) Borrower hereby pledges to Silicon the
cash or cash equivalents delivered from time to time to Silicon as security in
respect of Borrower's outstanding Letters of Credit, Foreign Exchange Contracts,
and Cash Management Services (the "Ancillary Cash Security").


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        Borrower hereby confirms that the commitment of Silicon to extend credit
under the Loan Agreement and related loan documents is terminated as of the date
of this letter agreement, and, as of the date of this letter agreement, Silicon
has no further obligation to extend credit to or for the account of Borrower.

        Silicon agrees to release, without any recourse, representation, or
warranty and on and with effect from the date of this letter agreement, all of
its security interests and liens created under the Loan Agreement and related
documents as security for the Obligations under or in respect of the Loan
Agreement (other than the Ancillary Cash Security). In connection therewith,
Silicon hereby authorizes Borrower to file in the appropriate filing office(s)
such UCC termination statements as may be necessary to terminate, as of record,
the UCC financing statements previously filed by Silicon with respect to
Borrower. Silicon further agrees, as promptly as practicable and at Borrower's
sole expense, to execute and deliver any and all other lien releases and other
similar discharge or release documents (and if applicable, in recordable form)
that (i) Borrower reasonably may request to release, as of record and without
any recourse, representation, or warranty, the security interests and all other
notices of security interests and liens previously filed by Silicon with respect
to the Obligations (other than the Ancillary Cash Security), and (ii) at
Silicon's election, Borrower prepares.

        Silicon makes no representation or warranty under or in connection with
this letter agreement, including without limitation with respect to the state of
title to any collateral securing the Obligations.

[remainder of page intentionally left blank; signature page follows]


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This letter agreement may be executed by each party on a separate counterpart,
each of which when so executed and delivered shall be an original, but all of
which together shall constitute one agreement. Delivery of an executed
counterpart of this letter agreement by telefacsimile shall be equally as
effective as delivery of an original executed counterpart of this letter
agreement.

                                        Sincerely yours,

                                        SILICON VALLEY BANK


                                        By /s/ [SIGNATURE ILLEGIBLE]
                                           ----------------------------------
                                        Title Sr. Vice President
                                              -------------------------------


Accepted and agreed:

MTI TECHNOLOGY CORPORATION


By /s/ MARK A. FRANZEN
   ---------------------------------
Title Chief Financial Officer
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Acknowledged:

MTI TECHNOLOGY B.V.,
a company organized under the laws of The Netherlands


By /s/ THOMAS P. RAIMONDI, JR.
   ---------------------------------
Title Vice Chairman, President & CEO
      ------------------------------


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