The NI ftp site contains a Application builder update for 4.0:
ftp://ftp.ni.com/support/labview/updates/windows/appbuild/lv4abud.zip with files dated 3-20-1996 (inside zip file).
From the README:
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- File Descriptions -
lv4abud.zip:
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LabVIEW Application Builder 4.0 update for LabVIEW 4.0
Windows 3.x/95/NT versions only
Disk 1 of 1
Copyright 1996 National Instruments Corporation
All rights reserved
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Sorry, 4.0 is too old for me to remember much about such details, but I would just try to download and install this.