Go to a DOS prompt. Type in debug at the C: prompt.

Enter in the following commands:

Blue what you type in.

Pink what is displayed on the screen. (DO NOT TYPE THIS IN!)

Black this is useful information. (DO NOT TYPE THIS IN!)

To verify which communications ports are being detected:

----------------------------------------------------------------------

-D 40:0 B (ENTER)

0040:0000 F8 03 F8 02 00 00 00 00 78 03 00 00 ...........x...

-Q (ENTER)

Com1's I/O address is written as F8 03 above. This is Debugs way of saying "I see port 03F8." Com 1 is O.K.

Com2's I/O address is written as F8 02 above. This is Debugs way of saying "I see port 02F8." Com 2 is O.K.

Com3's I/O address is written as 00 00 above. This is Debugs way of saying I don't see this port.

Com4's I/O address is written as 00 00 above. This is Debugs way of saying I don't see this port.

LPT1's I/O address is written as 78 03 above. This is Debugs way of saying "I see port 0378." LPT 1 is O.K.

LPT2's I/O address is written as 00 00 above. This is Debugs way of saying I don't see this port.