this is sraight from microsoft :
use these 3 search words (all) :
option pack install
or
copy this link
http://support.microsoft.com/support/kb/articles/Q195/0/15.ASP?LN=EN-US&SD=gn&FR=0&qry=option%20pack%20install&rnk=6&src=DHCS_MSPSS_gn_SRCH&SPR=NTW40
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Option Pack Installation Conflicts with Service Pack 4
The information in this article applies to:
Microsoft Windows NT Server versions 4.0 SP4, 4.0 SP5, 4.0 SP6, 4.0 SP6a
Microsoft Windows NT Workstationversions 4.0 SP4, 4.0 SP5, 4.0 SP6, 4.0 SP6a
SYMPTOMS
When you install Windows NT Option Pack on a computer that already has Windows NT 4.0 Service Pack 4 (or greater) installed, the following error message is displayed:
Setup detected that Windows NT 4.0 SP4 or greater is installed on your machine. We haven't tested this product on SP4. Do you wish to proceed?
Click OK to continue the installation. After the setup program has completed and the computer has restarted, you can reapply Windows NT 4.0 Service Pack 4.
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