DOS Norton NCD under VP/ix causes panic

[Raymond Nijssen]

I have a 386 running ISC 386/ix release 2.0.1, and AT&T's Simultask (=VP/ix)
version 2.0, and it runs quite stable, except when I start Norton's NCD
program (the DOS version under VP/ix): it first scans the entiry dirtree
of my (native) DOS partion, which is mounted by the line
mount -f DOS /dev/dsk/0p1 /dos
Second, it finds way too much directory entries, and then, the HD controller
activity LED comes solid for a number of seconds, soon followed by a
panic: kernel mode trap 0x000000E, a registerdump, etcetera.

I wonder how a program like NCD, which uses, as it seems to me, only MS-DOS
calls, can cause not only the VP/ix application to crash, which would be
comparably bearable, but also the whole system. Minor detail: the DOS      
partition was damaged severely, and could only be fixed after a number of
manual fixes and restores.

I would like to know if other users have the same experience and how 
these instabilities can be avoided in the future.

Greetings,
Raymond.

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raymond at ele.tue.nl
Raymond Nijssen