From: Lars-Einar Jansson <lars_einar DOT jansson AT 2 DOT sbbs DOT se>
To: opendos AT delorie DOT com, caldera-opendos AT rim DOT caldera DOT com
Date:          Sat, 21 Nov 1998 02:39:03 
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Subject:       Packed file is corrupt?
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Message-Id: <11181446546015@2.sbbs.se>
Reply-To: opendos AT delorie DOT com

I downloaded DR-DOS 7.02 some time ago to try on my old Philips P2230 
with i286 CPU, after having used MS-DOS 6.0 before. Recently, I even 
updated to DR-DOS 7.03 BETA.

When trying to launch a couple of applications residing on the C-
drive, among them PCTOOLS' PCShell, in a version from 1991, I got the 
error message "Packed file is corrupt". I'm not running any kind of 
disk-compression.

However, when trying to launch the same applications from Norton
Commander, 1988 version, everything seemed to be quite normal. Also,
when trying to launch the same applications from the commandline
after having booted the computer up from a floppy with DR-DOS 7.02 or 
MS-DOS 6.0, nothing peculiar happened.


ANOTHER PECULIARITY

I recently bought some software from the Swedish Postal Giro, in 
order to be able to pay my bills via modem. I chose an old DOS-
version of their software, in order for it to work properly on my old 
computer. The name of this software is "AviTel 3.33" which probably 
doesn't mean a thing to you. The program's configuration is 
automatically saved to a file called "avitel.bok".

Anyhow, when changing the configuration to suit my needs, the program 
refused to start anew, claiming there was something wrong with the 
configuration file - "unknown post" or something like that.

Then I tried to make the changes after having booted the computer 
with MS-DOS instead, and now it worked! The changed file could also 
be read by DR-DOS. 

Then I made the experiment just *looking* at the configuration
(without making any changes) and then finishing the program. With
MS-DOS the config-file now had a new time-stamp, but the same size. A
close scrutiny with PCShell in hex-read-mode revealed some
differences, though. Doing *exactly* the same thing with DR-DOS, both
7.02 and 7.03, the file also changed, but not in the same way, and
the length was also increased, from 503 bytes to 512 bytes. The file 
"looked at" with MS-DOS was still accepted by the program, whereas it 
rejected the file DR-DOS had been involved with.

I suppose one cannot expect 100% compatibility between different OS's 
and different versions thereof. 

Lars-Einar Jansson
Stockholm, Sweden
Stockholm, Sweden