SetWindowLong is not working on some computers

Question

Edit: More Information I've narrowed it down to certain applications on certain computers. I am trying to launch chrome in a full screen mode on a certain monitor. This works perfectly on most systems I have tested however we have run into a set of computers running Windows 7 Pro 32bit which are being moved and resized correctly, but their border and buttons are still intact.

I realize that chrome windows all spawn under a single chrome process and that their lifecycle is volatile, but we have been able to work around this using a separate data directory which keeps each chrome instance launched that way in it's own parent process. Chrome seems to be the only application we have problems launching full screen and only on one set of computers. When running calc.exe for instance it maximizes and removes the borders without any problems on all systems we have tested. I have confirmed that the version of chrome running on each system is the same. I would really appreciate it if anyone had more insight into either this problem, or ways of further troubleshooting the issue.

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I'm trying to run an application in a full screen mode using SetWindowLong and it's worked great up until the latest computer I tried it on. I am basically using the code referenced in this question: Removing window border?

This works fine on both of my laptops (Windows 7 Ultimate) and a couple work boxes that I have tested it on (Windows 7 POS Embedded) but it's not working on another computer at work (Windows 7 Professional). The SetWindowLong call is returning the expected value which indicates to me that it should be working, and the call to SetWindowPos works fine as it's resizing the window correctly, but the border and buttons are still there! It's functioning as if there was no call to SetWindowLong at all. I would greatly appreciate some help as I'm out of ideas at this point.

Edit: Here is the code in all it's 1AM red eyed glory. Pretty much a direct copy of the linked question.

int lStyle = GetWindowLong(process.MainWindowHandle, GWL_STYLE);
lStyle &= ~(WS_CAPTION | WS_THICKFRAME | WS_MINIMIZE | WS_MAXIMIZE | WS_SYSMENU);
_logger.Debug(String.Format("Style: {0}", lStyle)); // 369295360

var swlResult = SetWindowLong(process.MainWindowHandle, GWL_STYLE, lStyle);
_logger.Debug(String.Format("SetWindowLong: {0}", swlResult)); // 382664704

int lExStyle = GetWindowLong(process.MainWindowHandle, GWL_EXSTYLE);

lExStyle &= ~(WS_EX_DLGMODALFRAME | WS_EX_CLIENTEDGE | WS_EX_STATICEDGE);
SetWindowLong(process.MainWindowHandle, GWL_EXSTYLE, lExStyle);

Screen screen = GetDisplay(display);

return SetWindowPos(
    process.MainWindowHandle,
    HWND_TOPMOST,
    screen.WorkingArea.Left,
    screen.WorkingArea.Top,
    screen.WorkingArea.Width,
    screen.WorkingArea.Height,
    SetWindowPosFlags.SWP_FRAMECHANGED);

Answer 1

Found the problem. We are using LogMeIn for remote computer management, and it seems like their video mirror driver is causing problems on certain machines. Uninstalling their mirror driver, and restarting causes everything to work as expected.

It is also the case that this fails with out-of-date copies of XP (even SP3, and perhaps others). I have confirmed on over a dozen workstations that installing recommended updates resolves this issue. There were an average of updates needed on each, so it's hard to say which one did the trick, but apparently one of them did. Yet another reason to keep updates enabled.

Answer 2

Is the Windows 7 Professional system 64 bit? According to the documentation for SetWindowLong

This function has been superseded by the SetWindowLongPtr function. To write code that is compatible with both 32-bit and 64-bit versions of Windows, use the SetWindowLongPtr function.

Try modifying your code to call the SetWindowLongPtr function on 64 bit systems and see what happens.