HP 39g Master Manual page 205

The first task is to tell the program where to find the
aplet. Press the Change Directory button and use the
window that pops up to select the directory which
contains the aplet you want to transfer to the calculator.
Your program's window won't be the same as mine.
At the top of the window you'll see a message saying
"Please choose a directory" and, once you've chosen a directory you should
see "This directory contains hp 39g files" (if there are files there to be
downloaded). Press the OK button to select the directory.
Having connected the cable to the calculator,
change into the APLET view and press .
This time, choose Disk drive... from the menu
which pops up. Press ENTER.
If you receive the message shown right, then it
is probably caused by low batteries. However,
it may be because you have tried to download
the hp 38g version of the aplet instead of the
hp 39g/hp 39g+ version. It is normally only
received if the directory is empty or if one or
more files are damaged. Tell it and investigate.
If all has gone well, you should find that you
are looking at another pop-up menu which lists
the aplet you are trying to download, together
with the word 'Other..' If all you see is the
word 'Other..' then it may mean that you
haven't decompressed the aplet properly or
that the download was corrupted, and the aplet is not readable. This is
unlikely.
All else being well, if you now highlight the
name of the aplet and press , then you
will then be entertained to a series of
messages as the aplet and all its associated
programs transfer down the cable to your
calculator. If there is insufficient room on your
calculator then there will be an error message at some stage telling you this.
If this happens you will need to delete the incomplete aplet and however
many of its programs successfully downloaded. Given the amount of memory
on the hp 39g+, this is not likely.
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