Category : Unprotects for Games and Such
Archive   : CM2000.ZIP
Filename : CM2000.UNP

Unprotect for CHESSMASTER 2000 (version 1.01)

Contributed for your archival purposes only, by Dr. Skagway.

Kids, this one is real simple. The program disk has on it a hidden file
which is formatted in weird and wonderful ways, ways that your common,
ordinary, run of the mill copy programs can't handle. I wasn't even able
to get CopyIIPC or CopyWrite to work on this one. But then, I have a strange
homebrew computer. Anyway, the program CM.EXE on your Chessmaster disk looks
for verify failures from these bizarre sectors, and when found, runs the
program. If the sectors aren't weird (i.e., what you get with DISKCOPY)
then the program runs as a demo, and shuts down after a few minutes (nice
touch, more genteel than calling you a slimy bastard and disemboweling your
hard disk). This is a damn nice program, written by good people. Good people,
however, occasionally do stupid things like use copy protection. Use the
following information to back-up your copy and don't rip these folks off.

1. Make a copy of the distribution disk using DISKCOPY. Ignore the dire
warnings of unrecoverable read/write errors. The copy will have all
normal DOS sectors, with all of the necessary files on it. Only the
weird stuff won't get copied, but we don't need it. Put your original
disk away in a nice safe place where the Thought Police won't get at it.

2. Rename the file CM.EXE to something like CM.XXX, so we can use DEBUG.

A>debug cm.xxx
-

3. Search for the byte string B8 00 00 EB E7.

-s 0100 ffff b8 00 00 eb e7
XXXX:YYYY
-

This looks for a mov ax,0000 instruction that gets executed if the program
fails to find the weird sectors.

4. Assemble a new instruction here to fool the program.

-a XXXX:YYYY
XXXX:YYYY (type in mov AX,0001 then CR)
XXXX:YYYY+3 (type in a CR)
-

This instruction will return a code that indicates the presence of
weirdness, when in fact the sectors are normal.

5. Write the program back to disk.

-w
Writing ZZZZZ bytes
-q
A>

6. You now have a copy of Chessmaster that will run from the hard disk, and
that can be copied for archival purposes (not that saying "archival
purposes" will convert you scumballs that steal software, but I thought
I'd throw that in to cover my ass).

Bye for now.HqÆàӐ UJM