FOURTH AMENDMENT TO CREDIT AGREEMENT
AND FIRST AMENDMENT TO SECURITY AGREEMENT

     THIS FOURTH AMENDMENT TO CREDIT AGREEMENT AND FIRST AMENDMENT TO SECURITY
AGREEMENT (this "Amendment") is entered into as of January 31, 2013, by and
among the Lenders identified on the signature pages hereof (such Lenders,
together with their respective successors and permitted assigns, are referred to
hereinafter each individually as a "Lender" and collectively as the "Lenders"),
WELLS FARGO CAPITAL FINANCE, LLC, a Delaware limited liability company, as
administrative agent for the Lenders (in such capacity, "Agent") and QUANTUM
CORPORATION, a Delaware corporation ("Borrower").

     WHEREAS, Borrower, Agent, and Lenders are parties to that certain Credit
Agreement dated as of March 29, 2012 (as amended, modified or supplemented from
time to time, the "Credit Agreement");

     WHEREAS, Borrower and Agent are parties to that certain Security Agreement
dated as of March 29, 2012 (as amended, modified or supplemented from time to
time, the "Security Agreement"); and

     WHEREAS, Borrower, Agent and Lenders have agreed to amend (a) the Credit
Agreement in certain respects and (b) the Security Agreement in certain
respects, in each case subject to the terms and conditions contained herein.

     NOW THEREFORE, in consideration of the premises and mutual agreements
herein contained, the parties hereto agree as follows:

     1. Defined Terms. Unless otherwise defined herein, capitalized terms used
herein shall have the meanings ascribed to such terms in the Credit Agreement.

     2. Amendments to Credit Agreement. Subject to the satisfaction of the
conditions set forth in Section 6 below and in reliance upon the representations
and warranties of Borrower set forth in Section 7 below, the Credit Agreement is
amended as follows:

     (A) Section 2.10(c) of the Credit Agreement is hereby amended and restated
in its entirety, as follows:

          "(c) Field Examination and Other Fees. Borrower shall pay to Agent,
field examination, appraisal, and valuation fees and charges, as and when
incurred or chargeable, as follows: (i) a fee of $1,000 per day, per examiner,
plus reasonable and documented out-of-pocket expenses (including travel, meals,
and lodging), for each field examination of Borrower performed by personnel
employed by Agent, (ii) if implemented, a fee of $1,000 per day, per Person,
plus reasonable and documented out-of-pocket expenses, for the establishment of
electronic collateral reporting and (iii) the reasonable and documented fees or
charges paid or incurred by Agent if it elects to employ the services of one or
more third Persons to perform field examinations of Borrower or its
Subsidiaries, to appraise the Collateral or any portion thereof, or to assess
Borrower's or its Subsidiaries' business valuation; provided, that (x) so long
as (1) no Event of Default shall have occurred and be continuing, (2) Liquidity
is not less than $18,500,000 and (3) Pure Availability is not less than
$11,200,000, Borrower shall not be obligated to reimburse Agent for any field
examinations, appraisals or intellectual property valuations and Agent shall not
have the right to conduct more than 1 field examination and 1 appraisal of each
type of Collateral during any calendar year, and (y) if (1) an Event of Default
has occurred and is continuing, (2) Liquidity, as of any date, is less than
$18,500,000 or (3) Pure Availability, as of any date, is less than $11,200,000,
Borrower shall be obligated to reimburse Agent for no more than 2 field
examinations during any calendar year, no more than 1 appraisal of each type of
Collateral during any calendar year, and no more than 1 intellectual property
valuation during any calendar year and Agent shall have the right to conduct, at
its sole expense, field examinations, appraisals and intellectual property
valuations without limitation."

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     (B) The last sentence of Section 6.9(b) of the Credit Agreement is hereby
amended and restated in its entirety, as follows:

          "Agent hereby agrees that it will not issue such a "Notice of
Exclusive Control" or equivalent notice to the applicable depository bank unless
(x) an Event of Default has occurred and is continuing, (y) Liquidity, as of any
date, is less than $18,500,000 or (z) Pure Availability, as of any date, is less
than $11,200,000."

     (C) Section 7 of the Credit Agreement is hereby amended and restated in its
entirety, as follows:

          "7. FINANCIAL COVENANTS.

          Borrower covenants and agrees that, until termination of all of the
Commitments and payment in full of the Obligations, commencing on the date on
which a Financial Covenant Period begins and measured as of the end of the
fiscal quarter immediately preceding the date on which a Financial Covenant
Period first begins and as of each fiscal quarter end thereafter during such
Financial Covenant Period, Borrower will:

          (a) Fixed Charge Coverage Ratio. Have a Fixed Charge Coverage Ratio,
measured on a quarter-end basis, of at least 1.10 for the trailing 12-month
period ending on the last day of such fiscal quarter.

          (b) [Intentionally Omitted].

     (D) The definition of "Borrowing Base" contained in Schedule 1.1 of the
Credit Agreement is hereby amended and restated in its entirety, as follows:

          ""Borrowing Base" means, as of any date of determination, the result
of:

               (a) 100% of Qualified Cash, plus

               (b) the Accounts Component, plus

               (c) the lesser of

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                    (i) 50% of the Net Book Value of Borrower's and the other
Loan Parties' Inventory (other than Service Inventory) located in the United
States consisting of raw materials and finished goods as of such date; provided
that no more than $5,000,000 of such Inventory shall be located at locations not
identified on Schedule 4.24, and

                    (ii) the Accounts Component, minus

               (d) the aggregate amount of reserves, if any, established by
Agent under Section 2.1(c) of the Agreement."

     (E) Clause (b)(x) of the definition of "EBITDA" contained in Schedule 1.1
of the Credit Agreement is hereby amended and restated in its entirety, as
follows:

          "(x) capitalized debt issuance costs arising with respect to any
Permitted Refinancing or repayment of the Convertible Subordinated Debt and/or
the 2012 Convertible Subordinated Debt up to an aggregate amount not to exceed
$6,500,000,"

     (F) The definition of "Maximum Revolver Amount" contained in Schedule 1.1
of the Credit Agreement is hereby amended and restated in its entirety, as
follows:

          ""Maximum Revolver Amount" means $55,000,000, decreased by the amount
of reductions in the Revolver Commitments made in accordance with Section 2.4(c)
of the Agreement."

     (G) The following definitions are hereby added to Schedule 1.1 of the
Credit Agreement, inserted in appropriate alphabetical order:

          ""Financial Covenant Period" means a period which shall commence on
any date (the "Commencement Date") on which (a) Liquidity, as of such date, is
less than $16,500,000 or (b) Pure Availability, as of such date, is less than
$10,000,000, and shall continue until the later of:

          (a) the date that is the last day of the first full fiscal quarter
after the Commencement Date, and

          (b) the last day of the fiscal quarter in which, for a period of sixty
(60) consecutive days after the Commencement Date, (x) Liquidity, as of each
such date, is greater than or equal to $16,500,000 and (y) Pure Availability, as
of each such date, is greater than or equal to $10,000,000.

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          ""Pure Availability" means, as of any date of determination, an amount
equal to (a) Liquidity as of such date, minus (b) the amount of Qualified Cash
as of such date."

     (H) The definition of "Revolver Sub-Facility Amount" is hereby deleted from
Schedule 1.1 of the Credit Agreement in its entirety.

     (I) Exhibit B-1 to the Credit Agreement is hereby amended and restated in
its entirety as set forth on Exhibit A hereto.

     (J) Exhibit C-1 to the Credit Agreement is hereby amended and restated in
its entirety as set forth on Exhibit B hereto.

     (K) Schedule C-1 to the Credit Agreement is hereby amended and restated in
its entirety as set forth on Exhibit C hereto.

     (L) Schedule 5.1 to the Credit Agreement is hereby amended and restated in
its entirety as set forth on Exhibit D hereto.

     (M) Schedule 5.2 to the Credit Agreement is hereby amended and restated in
its entirety as set forth on Exhibit E hereto.

     3. Amendments to Security Agreement. Subject to the satisfaction of the
conditions set forth in Section 6 below and in reliance upon the representations
and warranties of Borrower set forth in Section 7 below, the Security Agreement
is amended as follows:

     (A) The definition of "Triggering Event" contained in Section 1(a) of the
Security Agreement is hereby amended and restated in its entirety, as follows:

          ""Triggering Event" means, as of any date of determination, that (A)
an Event of Default has occurred as of such date, (B) Liquidity, as of such
date, is less than $18,500,000 or (C) Pure Availability, as of such date, is
less than $11,200,000."

     (B) Clause (i) of Section 6(h) of the Security Agreement is hereby amended
and restated in its entirety, as follows:

          "(i) If Grantor shall acquire, obtain, receive or become entitled to
receive after the Closing Date any Pledged Interests constituting Collateral
having value in the amount of $750,000 or more, individually, or having value in
the aggregate for all Pledged Interests of $2,000,000 or more, it shall promptly
(and in any event concurrently with the next required delivery of the Compliance
Certificate (or, if an Event of Default has occurred and is continuing, when
requested by Agent)) deliver to Agent a duly executed Pledged Interests Addendum
identifying such Pledged Interests;"

     4. Continuing Effect. Except as expressly set forth in Sections 2 and 3 of
this Amendment, nothing in this Amendment shall constitute a modification or
alteration of the terms, conditions or covenants of the Credit Agreement, the
Security Agreement or any other Loan Document, or a waiver of any other terms or
provisions thereof, and the Credit Agreement, the Security Agreement and the
other Loan Documents shall remain unchanged and shall continue in full force and
effect, in each case as amended hereby.

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     5. Reaffirmation and Confirmation. Borrower hereby ratifies, affirms,
acknowledges and agrees that the Credit Agreement, the Security Agreement and
the other Loan Documents represent the valid, enforceable and collectible
obligations of Borrower, and further acknowledges that there are no existing
claims, defenses, personal or otherwise, or rights of setoff whatsoever with
respect to the Credit Agreement, the Security Agreement or any other Loan
Document. Borrower hereby agrees that this Amendment in no way acts as a release
or relinquishment of the Liens and rights securing payments of the Obligations.
The Liens and rights securing payment of the Obligations are hereby ratified and
confirmed by Borrower in all respects.

     6. Conditions to Effectiveness. This Amendment shall become effective as of
the date hereof and upon the satisfaction of the following conditions precedent:

     (a) Each party hereto shall have executed and delivered this Amendment to
Agent;

     (b) Agent shall have received the Fourth Amendment Fee referred to below;
and

     (c) No Default or Event of Default shall have occurred and be continuing on
the date hereof or as of the date of the effectiveness of this Amendment.

     7. Representations and Warranties. In order to induce Agent and Lenders to
enter into this Amendment, Borrower hereby represents and warrants to Agent and
Lenders, after giving effect to this Amendment:

     (a) All representations and warranties contained in the Credit Agreement,
the Security Agreement and the other Loan Documents are true and correct in all
material respects (except that such materiality qualifier shall not be
applicable to any representations and warranties that already are qualified or
modified by materiality in the text thereof) on the date of this Amendment, as
though made on and as of such date (except to the extent that such
representations and warranties relate solely to an earlier date, in which case
such representations and warranties shall be true and correct in all material
respects (except that such materiality qualifier shall not be applicable to any
representations and warranties that already are qualified or modified by
materiality in the text thereof) as of such earlier date);

     (b) No Default or Event of Default has occurred and is continuing; and

     (c) This Amendment, the Credit Agreement, as modified hereby, and the
Security Agreement, as modified hereby, constitute legal, valid and binding
obligations of Borrower and are enforceable against Borrower in accordance with
their respective terms.

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     8. Fourth Amendment Fee. Borrower shall pay to Agent, for the ratable
benefit of the Lenders based on their respective Pro Rata Shares, a fee equal to
$20,000 (the "Fourth Amendment Fee") which shall be fully earned and due and
payable on the date hereof.

     9. Miscellaneous.

     (a) Expenses. Notwithstanding anything in the Credit Agreement, the
Security Agreement or any other Loan Document to the contrary, solely for
purposes of this Amendment, Borrower shall not be responsible to pay the costs
or expenses of Agent or any Lender (including any fees or expenses of counsel
for Agent or any Lender) in connection with the preparation, negotiation,
execution, delivery and/or administration of this Amendment or any other
instruments or documents provided for herein or delivered or to be delivered
hereunder or in connection herewith.

     (b) Governing Law. This Amendment shall be a contract made under and
governed by the internal laws of the State of California.

     (c) Counterparts. This Amendment may be executed in any number of
counterparts, and by the parties hereto on the same or separate counterparts,
and each such counterpart, when executed and delivered, shall be deemed to be an
original, but all such counterparts shall together constitute but one and the
same Amendment.

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

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     IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed by their respective officers thereunto duly authorized and delivered as
of the date first above written.

QUANTUM CORPORATION a Delaware corporation     By: /s/ Linda M. Breard   Title:
SVP-CFO       WELLS FARGO CAPITAL FINANCE, LLC, as Agent and as a Lender     By:
/s/ Amelie Yehros   Title: SVP       SILICON VALLEY BANK, as a Lender     By:
/s/ Christopher L. Snider   Title:     Managing Director  

Signature Page to Fourth Amendment to Credit Agreement and First Amendment to
Security Agreement

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EXHIBIT A

Exhibit B-1

Form of Borrowing Base Certificate

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EXHIBIT B

EXHIBIT C-1

FORM OF COMPLIANCE CERTIFICATE

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EXHIBIT C

Schedule C-1

Revolver Commitments

Lender Revolver Commitment Total Commitment Wells Fargo Capital Finance, LLC
$36,666,666.67 $36,666,666.67 Silicon Valley Bank $18,333,333.33 $18,333,333.33
  All Lenders $55,000,000.00 $55,000,000.00

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EXHIBIT D

Schedule 5.1

     Borrower will deliver to Agent, with copies to each Lender, each of the
financial statements, reports, or other items set forth set forth below at the
following times in form satisfactory to Agent:

as soon as available, but in any event within 30 days (45 days in the case of a
month that is the end of one of Borrower's fiscal quarters) after the end of
each month during each of Borrower's fiscal years

(a) an unaudited consolidated and consolidating balance sheet, income statement,
calculation of EBITDA, and, solely in the case of a month that is the end of one
of Borrower's fiscal quarters, statement of cash flow, in each case, covering
Borrower's and its Subsidiaries' operations during such period.

(i) after the occurrence and during the continuance of a Default or an Event of
Default in any month or (ii) if, at any time, the Revolver Usage during a month
exceeds $15,000,000, as soon as available, but in any event within 30 days after
the end of such month during each of Borrower's fiscal years (other than a month
that is the end of one of Borrower's fiscal quarters) 

(b) a Compliance Certificate.

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as soon as available, but in any event within 45 days after the end of each
month that is the end of one of Borrower's fiscal quarters during each of
Borrower's fiscal years

(c) a Compliance Certificate.

as soon as available, but in any event within 90 days after the end of each of
Borrower's fiscal years (the "Annual Deadline")

(d) consolidated and consolidating financial statements of Borrower and its
Subsidiaries for each such fiscal year, which, in the case of the consolidated
financial statements, are audited by independent certified public accountants
reasonably acceptable to Agent and certified, without any qualifications
(including any (A) "going concern" or like qualification or exception, (B)
qualification or exception as to the scope of such audit, or (C) qualification
which relates to the treatment or classification of any item and which, as a
condition to the removal of such qualification, would require an adjustment to
such item, the effect of which would, subject to Section 1.2 of the Agreement,
be to cause any noncompliance with the provisions of Section 7), by such
accountants to have been prepared in accordance with GAAP (such audited
financial statements to include a balance sheet, income statement, and statement
of cash flow and, if prepared, such accountants' letter to management), and

(e) a Compliance Certificate.

provided, however, that if Borrower has filed any of the items listed in clause
(c) above in its Form 10-K annual report with the SEC within the applicable
Annual Deadline, then Borrower shall (i) provide Agent written notice (in the
Compliance Certificate or elsewhere) within the applicable Annual Deadline that
Borrower has filed its Form 10-K annual report with the SEC and (ii) deliver to
Agent by the applicable Annual Deadline copies of any items listed in clause (c)
above that were not filed with the SEC.

as soon as available, but in any event within 45 days after the start of each of
Borrower's fiscal years,

(f) copies of Borrower's Projections, in form (including as to scope and
underlying assumptions) reasonably satisfactory to Agent, in its Permitted
Discretion, for the forthcoming 3 years, year by year, and for the forthcoming
fiscal year, quarter by quarter, certified by the chief financial officer of
Borrower as being such officer's good faith estimate of the financial
performance of Borrower during the period covered thereby.

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if and when filed by Borrower (but only if requested by Agent)

(g) Form 10-Q quarterly reports, Form 10-K annual reports, and Form 8-K current
reports,

(h) any other filings made by Borrower with the SEC, and

(i) any other information that is provided by Borrower to its shareholders
generally.

promptly, but in any event within 5 Business Days after Borrower has knowledge
of any event or condition that constitutes a Default or an Event of Default,

(j) notice of such event or condition and a statement of the curative action
that Borrower proposes to take with respect thereto.

promptly after the commencement thereof, but in any event within 5 Business Days
after the service of process with respect thereto on Borrower or any of its
Subsidiaries,

(k) notice of all actions, suits, or proceedings brought by or against Borrower
or any of its Subsidiaries before any Governmental Authority which reasonably
could be expected to result in a Material Adverse Effect.

upon the request of Agent,

(l) any other information reasonably requested relating to the financial
condition of Borrower or its Subsidiaries.

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EXHIBIT E

Schedule 5.2

     Borrower will provide Agent (and if so requested by Agent, with copies for
each Lender) with each of the documents set forth below at the following times
in form satisfactory to Agent:

Monthly (no later than the 30th day after the end of each month)

(a) a Borrowing Base Certificate,

(b) a detailed report regarding Borrower's and its Subsidiaries' cash and Cash
Equivalents, including an indication of which amounts constitute Qualified Cash,
and

(c) if (i) an Event of Default has occurred and is continuing, (ii) Liquidity,
as of any date, is less than $18,500,000 or (iii) Pure Availability, as of any
date, is less than $11,200,000

, a reconciliation of Accounts, trade accounts payable, and Inventory of
Borrower's general ledger accounts to its monthly financial statements including
any book reserves related to each category.

Upon request by Agent

(d) such other reports as to the Collateral or the financial condition of
Borrower and its Subsidiaries, as Agent may reasonably request.

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