CNCpro Parallel port problem

I am using DeskNC in an IBM Thinkpad 760C to Dan's 2A board controlling a
Sherline Mill.
All perform fine.
I recently installed CNCpro which also works fine on initial installation.
Here is the problem: When the computer is shut down and rebooted, CNCpro
will no longer control the mill. No signals sent via the parallel port to
the control board. The x,y,z numbers on the screen change with jog commands
and G-Code programs run ok (watching the numbers change).
Re-loading CNCpro has no effect. The only way I can get it to run again,
is to remove the program via the Add/Remove switch, shut down the computer,
and then reload from the Zip disk, and reconfigure the port settings.
The LPT1 port is 03BC (according to system info) and that is the setting I
use from the CNCpro menu.
The port address used with DeskNC however, is 956. Don't recall why, but
arrived at that setting after consultation with Dan when I built the board
several years ago.
If anyone can shed some light onto this dilemma I would be most grateful.
Don