<PAGE>
                                        
                     AMENDMENT TO LEASE DATED OCTOBER 1, 1983

     This Amendment is to be attached, and will constitute an extension of 
the Lease dated October 1, 1983, by and between West Acres Office Park 
(hereafter referred to as "WAOP") as Landlord, and Great Plains Software 
O.C., Inc. (hereafter referred to as GPS) as Tenant, covering the continuing 
leasing of office space in the WAOP building.

<TABLE>
<CAPTION>
                                   TOTAL SQUARE     COST PER        MONTHLY
AREA DESCRIPTION                      FEET         SQUARE FOOT       RENTAL
----------------                      ----         -----------       ------
<S>                                <C>           <C>             <C>
BASEMENT:
1. NW Corner                            741          $8.53             527
2. Northwest (foss small repro)         520          $8.53             370
3. West Conf. Room                      300          $8.53             213
4. Northeast                          1,275          $8.53             906
5. Southwest Corner                   1,276          $8.53             907
6. South Middle                         280          $8.53             199

MAIN:
7. North                              5,355         $13.97           6,234
8. Southwest Corner                   3,912         $13.97           4,554

TOP:
9. North                              5,354         $13.97           6,233
10. South                             7,825         $13.97           9,110
                                      -----         ------           -----
                    TOTALS           26,838      Total Sq. Feet    $29,253
                                     ------                        -------

PARKING:
1. Garage (four paid at $45, five free)                               $180
2. Outside plug-ins (six paid at $7.50, three free)                     45

                            TOTAL MONTHLY RENTAL                   $29,478
</TABLE>

ADDITIONALLY, WAOP AND GPS HAVE AGREED TO THE FOLLOWING:

A.          This Amendment shall be effective July 1, 1998 and continue 
            through June 30, 2003.

B.          The rent listed above shall be effective July 1, 1998 and remain 
            fixed through June 30, 2002.  Thereafter, the rent shall be 
            adjusted as of July 1, 2002 by the change in the Midwest Consumer 
            Price Index from March 31, 2001 vs. March 31, 2002, not to exceed 
            3%.

C.          WAOP shall perform the following maintenance as soon as is 
            practicable, and no later than March 1, 1999: 
            i.   Replace the bathroom flooring

<PAGE>

D.          WAOP will install an external shut-off valve as soon as is 
            practicable, and no later than May 1, 1999.

E.          WAOP will continue to work on exterior building water leaks, with 
            a problem correction by October 1, 1998, if possible, and no 
            later than June 1, 1999.

F.          WAOP shall seek improvements in daytime maintenance as outlined 
            in the GPS letter of July 20, 1998, attached hereto.

G.          Between January 1 and May 31, 2002, GPS may give notice of early 
            termination by providing WAOP a six month notice of termination 
            AND a lump sum prepayment of four months rent beyond occupancy.  
            After June 1, 2002, GPS may give notice of early termination by 
            providing WAOP a four month notice of termination AND a lump sum 
            payment of three months rent beyond occupancy.

H.          At any time during the term of this lease extension, GPS shall 
            have the right to sublease any and all space to a related entity 
            or to a Partner/Developer, doing business with GPS.  GPS shall 
            also have the right to sublease any or all space to any business 
            entity, with the consent of WAOP, and such consent shall not be 
            unreasonably withheld.

Dated this   21    day of  December  , 1998.
           -------        -----------

WEST ACRES OFFICE PARK              GREAT PLAINS SOFTWARE O.C., INC.



By:   /s/ Dennis L. Fuhrman           By:   /s/ Jodi Uecker-Rust
    ------------------------              ---------------------------
          (as Landlord)                    (as Tenant)
      DENNIS L. FUHRMAN,                  JODI UECKER-RUST,
         GENERAL PARTNER                    EXECUTIVE VICE PRESIDENT


WITNESS:                            WITNESS:

/s/ Donna Hertges                     /s/ Doug R. Herman
-----------------------------       -------------------------------------
    Donna Hertges                         Doug R. Herman