<PAGE>
EXHIBIT 10.1

                                                                [EXECUTION COPY]

                       FOURTH AMENDMENT TO LOAN AGREEMENT

         FOURTH AMENDMENT, dated as of April 19, 2002 (this "Fourth Amendment"),
to the Fifth Amended and Restated Loan Agreement, dated March 17, 2000 (as
amended, the "Loan Agreement"), among METROCALL, INC. (the "Borrower"), the
banks and other financial institutions or entities from time to time parties
thereto (the "Lenders") and TORONTO DOMINION (TEXAS), INC., as administrative
agent (in such capacity, the "Administrative Agent").

                              W I T N E S S E T H:
                               - - - - - - - - - -

         WHEREAS, pursuant to the Loan Agreement, the Lenders have made certain
Loans and other financial accommodations to the Borrower which remain
outstanding;

         WHEREAS, the Borrower, the Administrative Agent and the Lenders wish to
preserve the ability of the Borrower to maintain cert tax attributes in
connection with any subsequent restructuring of its obligations under the Loan
Agreement; and

         WHEREAS, the Borrower has requested that the Administrative Agent and
the Lenders amend the Loan Agreement as set forth herein and the Administrative
Agent and the Lenders are willing to do so, but only on the terms and conditions
set forth herein;

         NOW, THEREFORE, in consideration of the promises contained herein and
for other good and valuable consideration the receipt and sufficiency of which
are hereby acknowledged, the parties hereto agree as follows:

                                    ARTICLE I
                                   DEFINITIONS

Section 1.1 General. Terms defined in the Loan Agreement and used herein shall,
unless otherwise indicated, have the meanings given to them in the Loan
Agreement. Terms defined and used in this Fourth Amendment shall have the
meanings given to them in this Fourth Amendment.

Section 1.2 Amendments to Definitions.  Article I of the Loan Agreement is
hereby amended by inserting the following new definitions in alphabetical order.

        "Existing Events of Default" has the meaning specified in Section 6.1 of
        the Fourth Amendment.

        "Fourth Amendment" means the Fourth Amendment to Loan Agreement, dated
        as of April 19, 2002.

        "Fourth Amendment Effective Date" has the meaning specified in Article
        IV of the Fourth Amendment.

        "Fourth Amendment Fee" has the meaning specified in Section 3.2 of the
        Fourth Amendment.



<PAGE>



                                   ARTICLE II
                                   AMENDMENTS

        Section 2.1 Amendment to Section 11.5 (Assignments). Section 11.5 of the
Loan Agreement is hereby amended by inserting the following as clause (g):

                  (g) Notwithstanding anything contained in this Agreement or
         the other Loan Documents to the contrary, (i) none of the Lenders may
         assign, participate or transfer any of their respective rights or
         interests under this Agreement or the other Loan Documents during the
         period from and including the Fourth Amendment Effective Date through
         and including October 21, 2002, without the prior written consent of
         the Majority Lenders, and (ii) any purported assignment, participation
         or other transfer entered into during said period, without the prior
         written consent of the Majority Lender, shall be ineffective and of no
         force or effect.

                                  ARTICLE III
                         REPRESENTATIONS AND AGREEMENTS

        Section 3.1 Prior Assignments and Participations. Each Lender signatory
hereto represents and warrants, severally, and not jointly, that, as of the
Fourth Amendment Effective Date, (i) the principal amounts of its respective
Commitments are equal to the amounts set forth opposite its signature below,
(ii) said Commitments were (a) entered into between said Lender and the Borrower
on or about March 17, 2000 or (b) acquired by said Lender pursuant to an
assignment effective as of the date set forth opposite its signature below and
(iii) that it has not entered into any assignment, participation or other
transfer with respect to its Commitments except as set forth opposite its
signature below.

        Section 3.2 Fee. The Borrower shall pay to the Administrative Agent, for
the ratable benefit of the Lenders, a fee in cash equal to $500,000 (the "Fourth
Amendment Fee"), payable on the Fourth Amendment Effective Date. Anything
contained herein to the contrary notwithstanding, the Fourth Amendment Fee shall
be deemed earned in full on the Fourth Amendment Effective Date.

                                   ARTICLE IV
                                 EFFECTIVE DATE

         This Fourth Amendment shall become effective as of the date first
written above (the "Fourth Amendment Effective Date") when each of the following
has been satisfied or waived in accordance with the terms hereof:

        (a) Receipt by the Administrative Agent of counterparts of this Fourth
Amendment duly executed and delivered by the Borrower;

        (b) Receipt by the Administrative Agent of counterparts of this Fourth
Amendment duly executed and delivered by the Majority Lenders and the
Administrative Agent; and

        (c) Receipt by the Administrative Agent of the Fourth Amendment Fee.


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                                   ARTICLE V
                                 INTERPRETATION

        Section 5.1 Continuing Effect of the Loan Agreement. The Borrower, the
Administrative Agent and the Lenders hereby acknowledge and agree that the Loan
Agreement and the other Loan Documents shall continue to be and shall remain
unchanged and in full force and effect in accordance with their terms, except as
expressly modified hereby. Any terms or conditions contained in this Fourth
Amendment shall control over any inconsistent terms or conditions in the Loan
Agreement or the other Loan Documents.

        Section 5.2 No Waiver; Other Defaults or Events of Default. Nothing
contained in this Fourth Amendment shall be construed or interpreted or is
intended as a waiver of or limitation on any rights, powers, privileges or
remedies that the Administrative Agent or the Lenders have or may have under the
Loan Agreement or any other Loan Document or applicable law on account of any
Default or Event of Default.

                                   ARTICLE VI
                                  MISCELLANEOUS

        Section 6.1 Representations and Warranties. The Borrower hereby
represents and warrants as of the date hereof that, after giving effect to this
Fourth Amendment, (a) no Default or Event of Default has occurred and is
continuing except that (i) as more fully set forth in the Administrative Agent's
Notice of Default, dated March 22, 2001, certain Events of Default under Section
8.1(k) of the Loan Agreement have occurred and are continuing, (ii) certain
Events of Default under Section 8.1(c) of the Loan Agreement have occurred and
are continuing based on the Borrower's default in the performance or observance
of the covenants contained in Sections 7.9 (Total Leverage Ratio), 7.10
(Annualized Operating Cash Flow to Pro Forma Debt Service Ratio) and 7.12
(Operating Cash Flow to New Cash Interest Expense Ratio) of the Loan Agreement,
(iii) certain Events of Default under Section 2.7(b)(ii) of the Loan Agreement
have and are continuing based on the Borrower's failure to make a principal
payment under the Facility B Commitment which was due on March 31, 2002
(collectively, the "Existing Events of Default") and (b) all representations and
warranties of the Borrower contained in the Loan Documents (with such term being
deemed to include this Fourth Amendment and the Loan Agreement) are true and
correct in all material respects with the same effect as if made on and as of
such date, except (i) to the extent any of such representations and warranties
relate to a specific date, in which case such representations and warranties
shall be deemed true and correct on and as of such date and (ii) as disclosed in
the Borrower's Form 10-K for the annual period ended December 31, 2001 (none of
which disclosures shall be deemed adopted, ratified or in any way approved by
the Administrative Agent or any of the Lenders).

        Section 6.2 Reaffirmation of Covenants. The Borrower hereby expressly
reaffirms each of the covenants made by them in the Loan Agreement and the other
Loan Documents.

        Section 6.3 Release. The Borrower on behalf of itself, its Subsidiaries
and its agents, acting in such capacity, hereby releases, waives, and forever
relinquishes all claims, demands, obligations, liabilities and causes of action
of whatever kind or nature, whether known or unknown, which any of them have,
may have, or might assert at the time of execution of this Fourth Amendment or
in the future against the Administrative Agent, the Lenders and/or their
respective parents, affiliates, participants, officers, directors, employees,
agents, attorneys, accountants, consultants, successors and assigns, directly or
indirectly, which occurred, existed, was taken, permitted or begun from the
beginning of time through the date hereof, arising out of, based upon, or in any
manner connected with (i) any transaction, event, circumstance, action, failure
to act or occurrence of any sort or type, whether known or unknown, with



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respect to the Loan Agreement, any other Loan Document and/or the administration
thereof or the Obligations created thereby, (ii) any discussions, commitments,
negotiations, conversations or communications with respect to the refinancing,
restructuring or collection of any Obligations related to the Loan Agreement,
any other Loan Document and/or the administration thereof or the Obligations
created thereby, or (iii) any matter related to the foregoing.

        Section 6.4 Reference to and Effect on the Loan Documents; Limited
Effect. On and after the date hereof and the satisfaction of the conditions
contained in Article IV of this Fourth Amendment, each reference in the Loan
Agreement to "this Agreement", "hereunder", "hereof" or words of like import
referring to the Loan Agreement, and each reference in the other Loan Documents
to "the Loan Agreement", "thereunder", "thereof" or words of like import
referring to the Loan Agreement, shall mean and be a reference to the Loan
Agreement as amended hereby. For purposes of the Loan Agreement, all of the
agreements of the Borrower contained in this Fourth Amendment shall be deemed to
be, and shall be, agreements under the Loan Agreement. The execution, delivery
and effectiveness of this Fourth Amendment shall not, except as expressly
provided herein, operate as a waiver of any right, power or remedy of any Lender
or any Agent under any of the Loan Documents, nor constitute a waiver of any
provisions of any of the Loan Documents. Except as expressly amended or waived
herein, all of the provisions and covenants of the Loan Agreement and the other
Loan Documents are and shall continue to remain in full force and effect in
accordance with the terms thereof and are hereby in all respects ratified and
confirmed.

        Section 6.5 Reservation of Rights. The Administrative Agent and each and
all of the Lenders hereby expressly reserve their rights, at any time to take
any and all actions, and to exercise any and all remedies, authorized or
permitted under the Loan Agreement or any of the Loan Documents, or available at
law or equity or otherwise. In addition, except as expressly provided herein,
the Administrative Agent and each of the Lenders do not waive and have not
waived any such rights or remedies by this Amendment or by their failure to act
upon any of the Existing Events of Default. Failure by the Administrative Agent
or any of the Lenders to exercise, or delay in exercising, any such rights or
remedies in the future shall not constitute a waiver of such rights or remedies
or of any Event of Default. Furthermore, any prior or current discussions or
course of conduct between the Administrative Agent and any of the Lenders or
their representatives, on the one hand, and the Borrower or its representatives,
on the other hand, is not and has not been intended to constitute a waiver of
any such rights or remedies, or an amendment of the Loan Agreement or any of the
Loan Documents.

        Section 6.6 Counterparts. This Fourth Amendment may be executed by one
or more of the parties hereto in any number of separate counterparts (which may
include counterparts delivered by facsimile transmission) and all of said
counterparts taken together shall be deemed to constitute one and the same
instrument. Any executed counterpart delivered by facsimile transmission shall
be effective for all purposes hereof.

        Section 6.7 GOVERNING LAW. THIS FOURTH AMENDMENT AND THE RIGHTS AND
OBLIGATIONS OF THE PARTIES UNDER THIS FOURTH AMENDMENT SHALL BE GOVERNED BY, AND
CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAW OF THE STATE OF NEW YORK.

                        [REMAINDER OF PAGE INTENTIONALLY
                        LEFT BLANK; SIGNATURES TO FOLLOW]

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<PAGE>

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


BORROWER:                            METROCALL, INC.


                                     By:___________________________________
                                        Name:______________________________
                                        Title:_____________________________


                                      S-1

<PAGE>


ADMINISTRATIVE AGENT AND               TORONTO DOMINION (TEXAS), INC., as
LENDERS:                               Administrative Agent and a Lender

<TABLE>
<CAPTION>
                     Commitments
Facility A           Facility B        Total
----------           ----------        -----
<S>              <C>               <C>                 <C>
(Revolver)             (Term)

$16,600,000          $5,000,000        $21,600,000         By:_______________________________________
Effective: On or about March 17, 2000                         Name: _________________________________
Transfers: None                                               Title: ________________________________
</TABLE>




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<PAGE>



<TABLE>
<CAPTION>
<S>                                                     <C>
                                                        FLEET NATIONAL BANK, as a Lender


$16,600,000       $5,000,000        $21,600,000         By:_______________________________________
Effective: On or about March 17, 2000                        Name: _______________________________
Transfers: None                                              Title: ______________________________
</TABLE>



                                      S-3

<PAGE>



<TABLE>
<CAPTION>
<S>                                                    <C>
                                                        FIRST UNION NATIONAL BANK, as a Lender


$16,600,000       $5,000,000        $21,600,000         By:_______________________________________
Effective: On or about March 17, 2000                      Name: _________________________________
Transfers:  None                                           Title: ________________________________
</TABLE>


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<PAGE>



<TABLE>
<CAPTION>
<S>                                                    <C>
                                                        COMMERCIAL LOAN FUNDING TRUST I, as a Lender
                                                        By:  Lehman Commercial Paper, Inc., not in its individual
                                                        capacity but solely as administrative agent


$0                $15,000,000       $15,000,000         By:_______________________________________
Effective: On or about March 17, 2000                        Name: _______________________________
Transfers:  None                                             Title: ______________________________
</TABLE>



                                      S-5
<PAGE>



<TABLE>
<CAPTION>
<S>                                                    <C>
                                                        MORGAN STANLEY SENIOR FUNDING, INC., as a Lender


$8,300,000        $5,000,000        $13,300,000         By:_______________________________________
Effective: On or about March 17, 2000                        Name: _______________________________
Transfers:  None                                             Title: ______________________________
</TABLE>



                                      S-6
<PAGE>



<TABLE>
<CAPTION>
<S>                                                     <C>
                                                        PNC BANK, NATIONAL ASSOCIATION, as a Lender
$8,300,000        $5,000,000        $13,300,000
Effective: On or about March 17, 2000                   By:_______________________________________
Transfers: 100% participation to affiliated entity           Name: _________________________________
effective _____________                                      Title: __________________________________
</TABLE>



                                      S-7
<PAGE>



<TABLE>
<CAPTION>
<S>                                                     <C>
                                                        ENDEAVOR L.L.C., as a Lender

$6,600,000        $5,000,000        $11,600,000
Effective: Acquired pursuant to an assignment           By:_______________________________________
effective October 2001                                       Name: _______________________________
Transfers:  None                                             Title: ______________________________
</TABLE>



                                      S-8
<PAGE>



<TABLE>
<CAPTION>
<S>                                                    <C>
                                                        CAPITAL CROSSOVER PARTNERS, as a Lender
$3,000,000        $5,000,000        $8,000,000
Effective: Acquired pursuant to assignments effective
(i) February 2002 ($5,000,000) and (ii) March  2002
($3,000,000)                                            By:_______________________________________
Transfers:  Participation of substantial portion of          Name: _______________________________
Commitments to affiliated entities                           Title: ______________________________
</TABLE>


                                      S-9
<PAGE>

<TABLE>
<CAPTION>
<S>                                                     <C>
                                                        BANK OF AMERICA, N.A., as a Lender
$7,000,000        $0                $7,000,000
Effective: Acquired pursuant to assignment effective
March 2002                                              By:_______________________________________
Transfers:  Assignment to Ingalls & Snyder LLC of          Name: _________________________________
100% of Commitments pending                                Title: ________________________________

TOTAL:
$83,000,000       $50,000,000       $133,000,000
</TABLE>

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