I have a Windows Service that runs the Excel Interop in order to automate the execution of various macros. However, I am running in a peculiar issue when I try to run a macro which access a database using Windows Authentication...
If the macro is run through the Windows Service, the workbook is opened and the macro is execution is started but the application hangs (presumably at the data access portion).
If, however, the macro is run through the Visual Studio debugger, using the same implementation as the service (they call the same class library), it executes, saves the workbook, and closes as expected.
I'm sure this has something to do with impersonation, but I can't seem to figure it out. I have the windows service running under my user and I have also modified the default COM properties in the Component Services to Impersonate instead of the default Identify.
Any help would be greatly appreciated, as it would be preferred to run as a windows service and not a console application.
Maybe I'm a bit late, but here I go anyway:
I had a similar issue and solved it by creating a Desktop folder in C:\Windows\SysWOW64\config\systemprofile and C:\Windows\System32\config\systemprofile.
It seems that Excel is not able to run under a specific user when used in a Windows service. Therefore, it runs with the LocalSystem service account, and it requires a Desktop folder in order to interact with Excel interop.
I have no further explanation, but it worked for me and it didn't cause any other know issue. I searched quite a lot for a definitive answer, but everything I found described the solution without specifying a reason.
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I have C# application acting as a scheduler. It runs various applications successfully. One of these applications (VB6) fails halfway through the job. If I execute this VB6 application directly with the exact same parameters, it completes successfully. The scheduler runs other VB6 applications successfully. Does anybody know what could cause this? What in the environment changes when you launch an application (VB6 exe) from within another application (C#)? Maybe there is an expert that can point me to something to help solve this?
I am adding more logging to the VB6 application and currently the error points to a routine executing SQL commands, but I have other applications executing the same code with no problem. At this stage I am stumped.
The following might be different
user account / user rights
working directory
environment variables
I suggest inspecting the VB6 application with Process Explorer and comparing against a working version.
OK, I found the problem. I started by rolling back the VB6 code two versions and proved that it worked. I then added small pieces of the new code and checking every time if it still works. I did not add back all the code (some were just cosmetic) and it is now working with the new functionality. It has taken a LOT of hours and it will take a lot more to determine what caused the original error, so I decided to take the win, because I cannot afford more hours.
This question may be some times funny for all. Created an application in c# but my problem is in implementing that, the application should not be stopped in any case with out system restart. How can i do this? I heard about circular reference what is it and how can i apply it in my windows application
if it can be done using windows service then service can also be stopped from task manager but i don't want my application to stop
you can not do this, since the application can be closed using Task Manger. So the only way is to create two processes first represent your app second to check if your app is closed run it again.
You could create a service, as suggested in one comment. This will prevent people without administrative controls from stopping it. If people do have administrative control, they will be able to stop your program quite easily.
I checked for tricks kids use to go around Net Nanny. The most common trick is to install a virtual machine and use that for accessing the network. Users who aren't administrators can't install Virtual Box or the like, so the service solution will work against these, as well.
Despite my thorough googling, I am still confused on this matter.
Let me explain my situation. I created a c# project which gives the user the ability to back up the database manually (via a button click). Now the user must be able to schedule a time at which the database back up will run automatically. To achieve this, I am planning on creating a service which is started via the windows scheduler when the set back up time is reached.
I will need the deploy the service along with the main project (In my head, the service will be a different project. Maybe I am wrong here.).
My question is how do I deploy the service when the user installs the main project?
PS: I am using c# express and sql 2008 R2 express.
What are you using to install the main application. Chances are you the said packaging tool will also have hooks for allowing you to install the service. For example, if you are using Wix to create a msi package to install the main application, then you can configure Wix to also install the service.
This google search will point you to relevant articles for the same.
If instead you are not using any installer tool, say you simply give the user a zip containing all executables, then you will need to manually install the service. This article is perfect to create a self installable service. You could use Process.Start to execute the installutil exe to acutally install/uninstall the service.
Edit1:
Building on Rup's comment to your question, you already have the code required to backup the database. All you need, is to be able to schedule this. Once the user enters a schedule in your UI, you can create the corresponding task in the Task Scheduler. Have that task execute your main application, passing in the argument -backup "dbName" or what ever info is needed for the before mentioned backup code to run.
You may use the following template [which is meant for a console app, but will work just fine for your gui app as well. All you will need to check is if any switches have been passed in, then do not start the gui, instead simple execute the backup function code.] ... There are also a lot of existing questions on StackOverflow on which commandline parsing tool to use ...
The approach I would take is create the project for the UI, create a project for the service. The service would be a windows service that would always be running and would be responsible for creating the scheduled task. (Rather than having a scheduled task start the service.) How you go about creating the scheduled task is fairly open, you could shell out AT, or you could do some COM interop with the TaskScheduler type libs. I hope this helps.
I have a WPF application that occasionally crashes, and say "not responding". Is there a way to detect if the program is not responding? And if so, restart the WPF application?
This will be a temporary fix until the bugs are fixed.
You could use the Application Recovery & Restart Manager API, which was introduced in Windows Vista. This is an unmanaged (C) API, however there are managed wrappers available in the Windows API Code Pack.
This is a good feature to add to your application anyway, as it provides the user with a nicer experience if (when!) you application crashes. You can even write a callback that persists information about what the user was doing, and then restore that state when the application restarts.
The most basic use of the API would be to just add the following line somewhere in application startup:
ApplicationRestartRecoveryManager.RegisterForApplicationRestart( new RestartSettings( "restart", RestartRestrictions.None ) );
Because this is a temporary fix while you debug the app, one possibility is to cheat and use a bootstrapper/startup app whose sole job is to monitor the problematic app. Start the problematic application via the System.Diagnostics.Process class's Start method, then occasionally monitor the returned Process' Responding property. If not responding, do what you need to do.
It's important that this only be done as a stopgap while you fix the real problem, of course. There are lots of little issues with doing something like this long-term.
Usually a mobile dev would not have to do this because the smart-minimise feature handles it.
But I need to do it myself because my mobile app is kicked off by a bootstrapper app.
The start menu icon kicks off the bottstrapper which downloads a target version from a web service, kicks it off and then closes. If the app gets minimised for whatever reason, the user would normally activate it again using the start menu icon. However, this kicks off the bootstrapper and results in a second copy of the client.
This question comes up everywhere on the net for desktop apps (and is in fact on this site). The usually cited solution is to use a combination of Process.GetProcessesByName combined with API calls to re-activate the process once found. Another solution is to create a controller class that inherits from some VisualBasic dll that I forget the name of. None of the solutions I have come across today are supported by the comapct framework.
So the actual question is a combination of:
Is there a compact framework alternative to Process.GetProcessesByName?
If not, what API call do I have to do instead?
I'm not sure if you found this yet or not, but MSDN has an article on creating a process manager application that has the info that I think you need.
The article reccomends using toolhelp.dll and has a pretty detailed looking walk-through for getting a list of running processes. It's for Visual Studio 2003, so you should probably be good with whatever version of VS.NET you're running.