Shareware Time Lock

 BBS: Inland Empire Archive
Date: 03-23-92 (11:36)             Number: 138
From: RICHARD VANNOY               Refer#: 59
  To: MARK BUTLER                   Recvd: NO  
Subj: Shareware Time Lock            Conf: (2) Quik_Bas
MB> 2.) A README.1ST file tells the user to run a small "install" utility
MB>     immediately before doing anything else to "initialize" the main
MB>     executable.

If you assume that they figure out your install program,
they could ignore it and go straight to the EXE.  How

GAME10.ZIP     The zipped file
GAME10.EXE     The install program (disguised)
DATA.BIN       The "real" program.

GAME does the following:
   - Zero out/erase the ZIP.
   - Write system date (ENCRYPTED!) to preassigned spot
     in DATA.BIN.
   - Erase GAME10.EXE (itself)
   - Rename DATA.BIN to GAME.EXE.
   - Chain to GAME.EXE.
The 10 in GAME10 is just a dummy (or real) version number
used for file identification, so the extension can be

The advantage could be that the user can't even COPY
GAME.EXE and distribute it, since it effectively has a
"time bomb" with the imbedded date.

MB> 4.) After destroying the original archive it then covertly writes
MB>     current system time and date in binary to the main executable.
MB>     When "test-run" period has elapsed a window comes up thanking the
MB>     user for trying it out, gives address where to order the game for
MB>     _real_ and then the game program promptly writes all zeros to
MB>     itself and commits suicide.

Or better yet, let the game play for about one third the
time needed to normally complete the game and then go to
the "special" closing screen.  Obviously, they will either
send the money or erase the game.  Not much need for you
to do it.

Also the screen could clearly say "You have gotten hold of
a demo copy that has expired.  Either:
    If this is your first use, tell the Sysop where you
       found this that he has a hacked demo, or
    Send $2.00 S&H for a new demo copy or
    Send $x.00 for the real thing.

> MegaMail 2.1b #0:Bug free, cheap, or on time.  Pick two!

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