Program freezing [Resolved--Oddly]

[Shaggy Hiker]

I'm not sure that this is the right audience, and I haven't gotten to spend ANY time diagnosing this yet (I just figured it out this morning), but I thought I might put it up on the board in case anybody had some suggestions.

I have a program that takes several days to run. Basically, I start it running on a system, then go away and do other things, checking on it occasionally. This seems to be running ok on two of the systems. There is a bug in it somewhere, since one of the systems eventually gave me a Object not set to an instance values, but that only arose after three days of constant running. A problem as intermittent as that will be darn hard to track down, but at least I know it is there.

On one of the systems, the screen goes to screen saver mode, then it shuts off. The OS is XP Pro. To recover from this sleep mode, I press any key and enter a password. However, when I recover from sleep mode, the program is locked up. According to CPU usage, it is still running, and appears to be doing something, but the form never refreshes itself. The program is running in a long loop, and every time through the loop it should hit a me.Refresh call. However, clicking on the program just tells me that the program is not responding. At that point, I use the task manager to end the program.

When I reload the program (it saves itself every so often), I find that it must have stopped running at some point fairly early on. I assume (I haven't played with it enough to do more than assume) that when the system goes into sleep mode, the program suspends. Naturally, this is not a good thing when the program takes about four days to complete.

My next step is to turn off sleep mode. However, I'm not sure why a running program would fail to respond once the system has been brought out of sleep mode. Other programs don't behave that way. Furthermore, this one may not be hung exactly, since CPU usage remains fairly high. What may be happening is that the loop is running, but the main window will not re-draw itself.

Any suggestions as to what could be causing it to perform like this?