Process runs, but app window does not display

[tmqrichard]

(First, sorry, I am very new to version 7)

I have an application that has worked pretty well on all previous versions of Windows, but now have a user on Windows 7 that is reporting the following behavior. I dont know if this is 7 issue or not, as the app is running on 7 systems also, tho not very many.

When they launch the program by doubleclicking the icon, an expected pop-up message appears (pertaining to software registration), and then instead of the main program window appearing, nothing does. But there is an icon for the program on the taskbar (clicking does nothing) and the process is running in the task list.

Internally, before the main program shows its form, it calls a registration DLL to check that out (hence the pop-up), and then continues with its start-up sequence.

Is there some situation peculiar to 7 that might be blocking the program from starting correctly?

 

[zigzag3143]

(First, sorry, I am very new to version 7)

I have an application that has worked pretty well on all previous versions of Windows, but now have a user on Windows 7 that is reporting the following behavior. I dont know if this is 7 issue or not, as the app is running on 7 systems also, tho not very many.

When they launch the program by doubleclicking the icon, an expected pop-up message appears (pertaining to software registration), and then instead of the main program window appearing, nothing does. But there is an icon for the program on the taskbar (clicking does nothing) and the process is running in the task list.

Internally, before the main program shows its form, it calls a registration DLL to check that out (hence the pop-up), and then continues with its start-up sequence.

Is there some situation peculiar to 7 that might be blocking the program from starting correctly?

Win 7 does have some additional security measures. We could tell you more if we knew something about the app.

win 7 has UAC (user account control) it may be interfering

Your app may need to be run (or installed) in compatibility mode.
(right click the installer>properties>compatibility>pick correct OS)

Let us know if you need help

Ken

 

[MilesAhead]

Is the registration dll put in System32 folder by any chance? On 64 bit Vista and W7 the 64 bit stuff is in System32 and the 32 bit stuff is in SysWow64.

If your installer manually tries to copy a 32 bit dll to System32 I'm not sure what happens, but it's not likely to work correctly.

If your installer is 64 bit aware then it's likely not the issue.

 

[tmqrichard]

Miles: No, the registration dll goes in Program Files with the other distributables.
Ken: The support person on the other end seems to favor a permissions issue, so we might try disabling UAC tomorrow. I've tried Compatibility mode (on my laptop, which has 7); the program doesn't seem to need it.

The first time the App runs, it hopes to copy a bunch of option files (text) from the distrib area into the users personal folder under the program name etc. I think that is taking place w/o problem, (ie we can make the folder, copy the files, etc) but I need to check it more carefully. Certainly we are not getting any UAC pop-ups.

 

[MilesAhead]

I'm just curious. Have you run it Ok on Vista? The biggest difference, other than drivers and all that, from XP to Vista/W7 is the composition and way graphics is handled. I haven't gotten into it that much myself. I just write small utilities. But the Aero/Composition/Glass stuff sometimes can raise havoc with apps that run fine in XP. Just a thought.

 

[tmqrichard]

Yes. No problems in Vista.

 

[MilesAhead]

Seems like a weirdie. The dude doesn't have a dongle on his machine by any chance? There's got to be something bizarre he's not telling you.

 

[brice]

Hello,

I have a similar problem. My app is launched from another, also written by me. When launched from this other application, the main window is not displayed. When directly launched, it is executing without any problem.

This application is running without any problem on both Windows Vista and XP

Did you find something to solve your problem ?

Best Regards,
Brice

 

[HarryO]

Like the original poster, my application runs, i.e. shows up on task bar, in task manager, and even writes a log file - but the GUI does not display.

But even stranger, it had been working fine on Windows 7 until suddenly the GUI stopped displaying on one user's computer.

And even stranger still... if I copy the executable to a different directory on the same computer and run it from there, it works fine, GUI displays, everything.

As far as I know, there have been no changes to the setup of the computer in question.

Any ideas would be very much appreciated.

Thanks!
Harry

 

[brice]

Hello HarryO,

I finally found the origin of my problem. The answer is described there:
wxWidgets Discussion Forum :: View topic - wxMSW : main frame not displayed

This problem is not specific to wxWidgets. In fact, in my case, it depended the way the process is launched. It was launched from another application, and this application was launching my main app with hide parameters (I don't remember the name of this parameter, but you can find it on MSDN).

On nearly all computers, this had no effect. And, when the main app was requesting to go in full-screen, this flag was overriden. But, sometimes, on Win-7, the strange behaviour descibed above happend.

I simply changed the parameters of the app laucnhing my main app and this now works fine.

I hope this will help you

BR,
Brice

 

[HarryO]

Hi Brice,

Thanks very much for your response. I think you are on to something regarding the app being launched from another process. In my case, the original chain of events is this:

1. user connects remotely to the computer in question
2. user runs app
3. app window does not display

Another contributing factor might be this: The app contains logic to position itself on the same screen location position as when it was when last closed. The computer it resides on has a dual monitor configuration. However, when remoting in, the user can only see one of these monitors at a time. Perhaps when he started the app, it positioned itself on the monitor his remote session could not see, thus leading to the problem?

I'll investigate. But thanks again for your help, it has been very useful!

Harry.