We have an old FPD 2.6 application running on a 486SX WS, DOS 6.22 - Novell 5.0.
The application is a data logger, and it uses Silverfox communication library to read from a 4 ports Digiboard. It is supposed to run 24 x 7, and for years it did... with the rare exceptions of server crashes.

Lately the computer locks in a strange way: the screen (which displays some indications about data being logged) goes up by few inches and the computer is locked. The only ways to restart it is the reset button or the power button.
There is no error message of any kind.
We checked all files, recreated all indexes, still locks occur, at irregular intervals, sometimes minutes, sometimes hours or days...

Did anybody experienced a similar symptom (the screen scrolling up)? Any ideas?

TIA,

dz