Random errors: what can cause them

External interaction:
And what if it was NOT your code, for once?

From time to time, you can have a problem that is coming entirely from the outside world... How do you make the difference? A lot of testing I'm afraid...

Of course, if the same problem happens on every PC and every OS, you can probably be sure that the problem is internal. But what if it happens only on some machines? Some of the coding problems described in the random page can give you these exact symptoms (Printing in the margins, printing on no printer, Not mapped network drive, using UpdateWindow on machines of different speed...)

Well, if you are not in one of the known problems that can seems to happen only on some machines, you can try one of the following things, on the machine on which the problem happen. All these thing should be tried one after the other, with a test reproducing the problem between each...

- First be sure that you cannot reproduce the problem by following the same steps on your development machine

- Then be sure that your OS is up to date (Windows Update is clearly NOT optional in that case), that your drivers are up to date too, and that any resident program running on the machine is of the last available version

- Deactivate any resident program (anti-virus, anti-spyware, firewall, and so on)... All these programs are trapping events and are sometime confusing a perfectly legitimate code with malicious behavior

- Also deactivate any automatic OS behavior (scheduled task, drive content indexation, etc.)

- Deactivate any non necessary service running on the machine

- If your program still doesn't work, uninstall these programs... I saw once an anti-virus being deactivated and still blocking the install of one of my software...

- If you have a machine with the same hardware available, you can also install only the OS, and try again... If you still have the problem, you are in either for a big debugging of your code, or a big hardware swapping feast... You can try to replace part of your machine (network card, video card, and so on, to see if your problem is driver related)

- And if none of that works, you can try to blame it on WinDev... Of course that will NOT solve your problem, but you can always ask PcSoft if they have ever seen the problem and found a solution... By the way, is your WinDev Up to date? Each update brings it's share of debug, and staying in the back of the class is not a good idea...