We at work are attempting to switch the OS that our systems run on from OS2 to WinNT. Part of this task is making sure that all of our applications (a mix of Win3.1, DOS, and OS2 apps) run acceptably under NT, and porting those applications that do not.

A major component of our system is a Foxpro 2.6 for DOS executable. This application has run perfectly well under OS2 for 4 years and on an in house Win95 box for over 2 years. Much to my horror, however, it does something inexplicable under NT.

The application runs anywhere from under 2 hours to up to 3 days, without a single complaint, and then at some point it simply disappears. It does not cause any errors that either Foxpro itself, NT, or the numerous traps and checks built into the application catch. It just goes away without a trace. The symptom is as if someone has come up and simply terminated the application. In fact, all of the monitoring that NT provides says exactly the same thing: "An task has exited".

It is not the case, however, that anyone is doing this. The box is stand alone, and the application has disappeared several times, while running on my desk with me sitting in front of it. I did not directly witness the event, but one minute it was running and the next, when I looked up from what I was reading, it was gone. No one close it down. (I make a point of this, because this was what one Microsoft technical support person insisted was happening, based on security entries that the system logged.)


The application maintains a log file, whereby it details it progress though the application. It records error messages to this and another log, as well as some simple progress messages. The application has never reported shutting down because of an error. And the progress messages that it leaves indicate that it is shutting [getting shut] down in about 25 to 30 different places. I have examined these locations in the code and can draw no correlation.

The only other clue (?) I have is that I set up another machine to run it on so that I could get more data points. This machine is a 486 with half the memory of the other, which is a Pentium. The slower machine shows occurrences of this problem at about 4 or 5 times the rate of the faster machine. Unfortunately, I don't have a clue as to how to interpret this information. One would think that there is a clue in there somewhere, but I can't imagine what it is. There are two many differences between the two machines, aside from the above two, that I couldn't possible eliminate enough variables to make the information meaningful. They are both running the same version of NT (with the exception mention below), and the same version of our product.

I have recently installed the NT Service Pack 3 on the slower machine (because it fails quicker), but this made absolutely no impact. The frequency and information output of the failure has remained the same.

I would sincerely appreciate any insight that you could lend. I am at my wits end with this problem. The biggest problem is that there is absolutely no data coming from anywhere which could possibly give me a hint as to where to focus. I have been in contact with MS Tech Support, but they have been little help.
Their biggest suggestion was to upgrade our version of Foxpro. This, however, is not acceptable for a multitude of reasons. Besides, why should it not run? Both products are theirs.

Thank you again for any assistance. In addition to posting back to this board, I can be emailed at pargang@aol.com.

Sincerely,
Steve Carlisle