We suggest that you use C:\Program Files\HPAC4.04 as the install directory. Make a note of the directory you choose. The rest of these instructions assume that you have chosen C:\Program Files\HPAC4.04.
Install HPAC taking all the defaults.
Add these lines to your jasS.ini file which will be in C:\Program Files\jas and C:\Program Files\Instantiations\VA Smalltalk\7.5\jas_oi if you are also running an open image.
[HPAC]
HpacPath=C:\Program Files\HPAC4.04
HpacTempdir=C:\Program Files\HPAC4.04\Temp
;this is where HPAC writes its temporary files; it can be any writable directory
Make sure that the directory C:\Program Files\HPAC4.04 and all its subdirectories are modifiable by all users of the system. You can check this by selecting the directory C:\Program Files\HPAC4.04 in Windows Explorer, right-clicking it, and then examining Security under Properties. Ask your system administrator if this is not clear.