I'm running my .NET 4.0 (C#) project in debug mode after I start VS2013. It runs just fine.
The second time I start it from VS, I get the Dialog box that says "Error while trying to run project: Unable to start program C:\path\to\file.exe"
The process is still alive in the Taskmanager when I dismiss the dialog box.
From Windows Explorer, I can run the program just fine. And after closing it, the process is gone too from the Task Manager.
A rebuild doesn't help.
Is this a common problem with a known solution?
I had an issue similar to this and I had to clear the component cache instruction can be found Here.
Hope this helps.
For my case, it cause by Platform target, you could force choose it to x86 or x64 which your project is:
Each Project's Properties > Build > Platform target
As I pointed out also here, the only solution that worked for me was to disable the ConEmu integration:
ConEmu → Settings → Integration → Default term → disable Force ConEmu as default terminal for console applications
Some users reported that it was enough for them to disable the Aggressive mode in that same settings tab; that wasn't the case for me though.
The topic is old, but this might help someone else.
So in my case I made a file in Visual Studio with .cp extension (accidentally deleted the last 'p') this made visual studio just "include" the the file and not mark it as a compilation unit, thus not compiling it, I looked the *.vcxproj file in a text editor and found out about this, so if you open the project file in a notepad or something just find your file at the bottom usually and change from <Item .../> to <ClCompile .../>
I was getting similar errors. I just had to restart visual studio. Sometime couple times a day.
I had a similar error and resolved it by cleaning the solution. Right-click the solution name in Solution Explorer and choose Clean Solution.
I found a solution here:
Please check "Use Managed Compatibility Mode" under Tools|->Options->Debugging->General.
I'm Brazilian, I don't speak English very well. I did this translation on google translator.
I know the topic is old, but it can still help someone.
I had this same problem in the following situation, I have a dual boot computer (linux debian 11 and windows 10). Inside debian, on my NTFS D disk, I created a folder to perform programming tests. After accessing that same folder with windows, I created a new project in visual studio inside that same folder that I had created in linux. The creation of the project went without problems, however when I tried to run the project (F5), I received the same error from this topic. I tried all the solutions I found on the internet, and nothing worked. I gave all permissions to my admin user and it still didn't work. Then I realized that even going straight to the folder where the application's executable was and clicking directly on it, I still received the access denied error message. So, I took the project out of the folder I had created in linux, and it worked. So, what I could conclude, is that because the folder where my project was was created in linux, for some reason, my windows didn't trust this folder, so it didn't allow running executables from inside that folder, even this one executable having been created by visual studio from within windows.
Just simply create a folder name as "projects" in c drive and copy paste the newly created project in it. Run the project by doing clean & Build or Rebuild method . It will work
open the folder which contains the solution in visual studio.
again, open your *.sln file by double clicking it inside the solution explore once opened try running the solution or rebuild the solution. once rebuild gets completed, it will open without error from next time.
My way of solving the error : error while trying to load project : Unable to start program and c:\Path\to\file.exe was simply by
First restart Visual Studio
Click the build icon
Select the rebuild option
Run the Program or Debug the Program
This was a weird one. Going to put what happened to me here because it might happen to someone else. Everything was fine with the app until suddenly after some fairly insignificant code changes I suddenly started getting this error. Visual Studio was compiling the executable just fine. But, the moment I tried to run it (either from Visual Studio or directly) the executable file would be automatically deleted right out of the Debug folder. Super odd--never seen anything like it. I began to get suspicious that perhaps an anti-virus or the OS was somehow identifying a checksum or some signature in the executable as "dangerous". Or perhaps some obscure compilation bug was corrupting the executable. So on a hunch I made another innocuous change (added a couple of lines of code to color code some text in a rich text box) and the problem went away.
I'll give you 2 versions of my problem to describe it, first the short version.
When I try to build my application it does that perfectly and my app works but when I try to rebuild it, that fails and gives an error message saying that 2 files are missing (bin/debug/MusicPlayer.exe and bin/debug/MusicPlayer.pdb). When I then try to build normally, it fails to with the same error.
Now the longer version:
The way this happened was quite out of nowhere, I program on 2 different locations (both in Visual Studio 2010 sp1) but to always have the recent version in the right place I copy the entire solution folder to a usb stick, this folder I copy over again on the other PC and use it to continue were I left off, I've done this many times without problem. Yesterday however, I got an exception while testing the app. But instead of showing this in my code, it was complaining that it could not find the program.cs file (it was there, but apparently it had a different checksum (md5) and it asked me to use this one. After a while I found what part of my code caused the exception and fixed it. Since then I haven't got that error anymore. But when I later tried to rebuild instead of build, it gave me the error described in the short version. I have tried to fix it, but apparently I was not very successful.
Basically, what I think it does is delete the files in the debug folder that need rebuilding and then gives me the error of missing files (the files that it deleted) and thus failing to rebuild succesfully because these deleted files the normal build option won't work to.
(What I then do is re-copy them from my usb to make the normal build work).
Don't know if it's important, but I program in C# and I'm still learning.
Also when I copied it to my usb I believe I had no errors and the app was working fine (except the part I fixed later, which I could not test at that location). And when I build the entire solution it gives some warning ==> "Assembly 'bun/debug/MusicPlayer.exe' is incorrectly specified as file" and this for 5 files.
Does anyone know how to fix this rebuild problem and if necessary the warnings?
Thanks in advance
(and sorry for my bad English)
OK it seems like you might be confusing yourself with your directory structure here. If you want to add Content or Resources (Images, Text Files, etc.) you should place them in a folder within your project (not called bin or obj). All your build files will go here. Instead place the Content in another folder and Right Click -> Properties and Set the build action to "Content" or "Resource" and set the Copy to Output Directory (bin folder) to "Do not Copy" or "Copy if newer."
The project is failing because you have the built executable "MusicPlayer.exe" in your project. So Visual Studio is trying to build an executable file in adding to the project. Restructure your directories or remove "MusicPlayer.exe" ever time your build your project.
Do you have any anti-virus software running? They can go way too aggressive on removable drives. You are actually continuously deleting and creating a runnable program on usb stick by recompiling.
Just a guess tho...
Sounds to me like you have a pre- or post-build event with a hardcoded path in it. Fix that using variables and it should be ok.
I've got a C# webforms app, that until today had been working just swimmingly.
Now today, all of a sudden, every time I try run the app, I get a file locking error:
Unable to copy file "obj\Debug\MyProject.exe" to "bin\Debug\MyProject.exe". The process cannot access the file "bin\Debug\MyProject.exe" because it is being used by another process.
Googling the error doesn't come up with anything beyond the obvious, i.e. VS thinks the file is locked. And it is definitely Visual Studio itself that locks the file, because when I close VS and reopen it, the project executes fine - the first time. When I try to run it a second time, I get the file locking error.
Closing VS and reopening every time I want to run the app is not a viable workaround! How do I find out what's locking the file, and stop it from getting locked?
EDIT: Another interesting discovery: I don't even have to run the app. Just compiling it once causes the file locking; I cannot compile twice in a row!
This problem is specific to one project in my solution. All other projects work fine and can be executed as many times as I like. It's only this one project that gets itself locked up.
I have found a simple solution which works for me. It goes like this:
When the problem occurs, just change the building configuration at the top (if in “Release” to “Debug” and vice versa), build and then change back to previous configuration and build again.
I suppose that changing the configuration releases the vcshost and devenv.
Well, I solved the problem myself - though I still have no clue why. I decided to isolate the problem by removing all files from the project, then re-adding them and determining that way which file was the source of my trouble. So, one by one I reintroduced files to the project, compiled & cleaned each step of the way... until... I added the last one...
... and everything still worked fine.
I did a compare to the source control of my original .csproj; no real differences. And even when I tried reverting to the previous version of the .csproj, it still worked.
Black magic. If it works, sometimes it's better not to ask why - just accept it and move on...
EDIT: The problem is a recurring one, and I believe I've isolated it to when I have the form designer open of an abstract/generic form at compile time.
Lesson learned: Make sure the Form Designer of any abstract or generic forms or controls is closed before you compile! If not, you have to close VS and reopen!
What we have discovered here, is the following:
In the project properties page, Debug tab, uncheck the "Enable visual studio hosting process".
I am unsure what this property is for, but it does the work once unchecked.
Solved by closing all instances of MSBuild.exe in the windows task manager
Actually you should want "Enable the Visual Studio hosting process" checked. At least for VS2010 anyway. And I also have:
if exist "$(TargetPath).locked" del "$(TargetPath).locked"
if exist "$(TargetPath)" if not exist "$(TargetPath).locked" move "$(TargetPath)" "$(TargetPath).locked"
in the pre-build options. This problem has dogged me for a very long time and it wasn't until John W. mentioned this check box that I even took notice that it existed and low and behold it was already unchecked.
Also notice that -app-vshost.exe runs in the background even when not debugging. Which is what makes it successfully build and run every time I guess. It wasn't running before. And I also tried cleaning out the debug and release folders and changing the target type constantly and nothing worked except as described above. My solution before was to just wait 5 minutes between builds, which got super annoying and time-consuming to get anything done. I haven't seen any change in behavior where it mattered what tabs where open or XNA vs windows form or designers being opened. This issue occurred in 32-bit or 64-bit builds and didn't matter if I killed an app with ALT-F4 or killing it with task manager, which would, in theory, not allow the app to close or release resources. At first I thought it was a garbage collection issue.
I have overcome this problem by renaming the locked file (using Windows Explorer). I was not allowed to delete the file, but renaming the locked file works!
Little late to answer, but I solved this by going to the properties of the project > tab "Debug" > unchecked "Enable the Visual Studio hosting process" option.
I solved this by deleting the folder bin\Debug and, possibly, restarting VS
Run this command from the Run box:
net stop iisadmin /y
and then
iisreset
worked for me.
vs 2003
For me, it was a Windows Service that was installed and running. Once I stopped it, the build was successful.
I had a similar error but during the deployment of the UWP application. Finally, I found out the process that used a file that caused this error and stopped it. Credits to this link. Copy-pasted version is below.
How to Solve the Issue?
One of the easiest ways to handle locked files or folders is to use Microsoft Sysinternals Process Explorer.
Identify what program is using a file
Using Process Explorer there is a simple way to find the program:
Open Process Explorer (running as administrator).
On the toolbar, find the gunsight icon on the right.
Drag the icon and drop it on the open file or folder that is locked.
The executable that is using the file will be highlighted in the Process Explorer main display list.
Identify which handle or DLL is using a file
Open Process Explorer (running as administrator).
Enter the keyboard shortcut Ctrl+F.
Alternatively, click the “Find” menu and select “Find a Handle or DLL”.
A search dialog box will open.
Type in the name of the locked file or other file of interest.
Partial names are usually sufficient.
Click the button “Search”.
A list will be generated.
There may be a number of entries.
And then kill this process.
Unfortunately none of the answers worked for me. This is what solved it:
Win Key + R and run resmon.exe. There you'll find the EXE process that VS claims to be using the file. Right click and end the process. Although you might get an Access Denied error message, it will be suspended and you'll be able to build again.
Recently ran into this problem when attempting to build a solution I am working on (not just a winforms proj).
In addition to build failure, I noticed that cleaning projects would quietly fail (checking the bin folder showed that the files had not actually been erased) and closing the Visual Studio did not end the devenv process - rather, it caused it to crash. Windows recovery process would then restart the Visual Studio.
After some trial and error, I found the problems only happened to me when I opened the solution from the "Recent" menu on starting up VS.
Opening the solution from File >> Open >> Project/Solution found it working as per usually.
Currently no idea why - will keep looking into this but for now, at least I can work!
Just check the references and remove the self-reference to the project.
Explanation: My problem started after creating a custom control and drag and drop it to the toolbox palette for use it in design forms. First appeared a warning saying that there was a redundance between the custom control source file (.cs) and the projects executable (.exe). On executing/debugging appeared the error: unable to access the (.exe) because it's being used (and it was true).
I literally removed the whole source code regarding the custom control and the problem still remained, until I checked out the references and it was referencing itself in order to be "able to" get the former custom control. I removed the reference and done!!
I had the same issue on my Xamarin application in visual studio and it was resolved by unplugging my test mobile device. The application was closed and the debugger was stopped but the error was still happening when trying to build or rebuild the solution. It only stopped after i unplugged the device because i had to receive a call.
Just to throw in my 2 cents. My issue was solved by opening Task Manager and killing the application. It was running in the background without any indication that it was running at all (no item in the task bar, no ui, nothing), but I am not sure why this happened. Obviously the debugger was not running and I only had a single instance of VS opened at the time. It amazes me that this is still happening in this VS 2017.
Perhaps I can add a build step that looks for the application running the background and kills it before starting the new one.
I had the same issue and could not rectify by using any of the methods mentioned in previous answers. I resolved the issue by killing all instances of "SSIS Debug Hist (32 bit)" in task manager and now working as normal.
I had this issue (and its an issue I have seen in other places not just VS).
It's caused by Dropbox (in my case). After editing some code and hitting run, sometimes dropbox immediately locks the file (so it can process it).
Solution 1.
Just hit run again
Solution 2.
Pause dropbox. (not good if your using dropbox as your cloud backup)
Solution 3.
Remove the build folder from dropboxes sync list.
Deleting Obj, retail and debug folder of the .NET project and re-building again worked for me.
This got me stuck for over two days, had to reclone the project and save the project folder in a different name, but today I found the solution from a microsoft dev forum.
solution:
Create a pre-build action in your project by going to project properties (right-click on the project in the solution explorer, and select the Properties option), select the Build Events tab. Add this code:
if exist "$(TargetPath).locked" del "$(TargetPath).locked"
if not exist "$(TargetPath).locked" move "$(TargetPath)" "$(TargetPath).locked"
This code will copy the file to a different name, and allows the build to continue successfully.
How is your web app configured? Does it run under Cassini (the tray web server) or IIS?
This shouldn't happen normally though. I think ProcessExplorer can tell you what files a process has locked. If not process explorer one of the other sysinternals tools.
One thing to try before even downloading one of the SI tools is to stop the Cassini web server, and seeing if that frees up the file.
What worked for me was restarting IIS
i had this same problem as well. changing the debug/release config didn't do the trick. at least not without building in between.
in my solution (winform) it was solved by opening the mainform of the winform in the designer. switching to code (F7). Then closing the code, closing the designer of the winform and rebuild all (ctrl-shift-B). This worked for me.
seems like some kind of handle from within the winform app (which runs a backgroundworker) still had a file handle on some of the other libraries used.
I had two instances of Visual Studio opened the same solution.
In my case there were some vstest processes running (with various names but all containing the string vstest). I had to terminate them in taskmgr.
Same error, solved by updating Google Nuget support packages
When I ended the process .Net Core Host, everything built fine. I didn't have to close Visual Studio or do change anything else.
For those who are developing in VS with Docker, restart the docker for windows service and the problem will be solved immediately.
Before restarting docker I tried all the mentioned answers, didn't find a msbuild.exe process running, also tried restarting VS without avail, only restarting docker worked.
One more solution: when the files get locked, blocking process is reported (something like "ServiceHub.Host.CLR.x64 (7764)") with it's id in parentheses.
To get rid of the process, open PowerShell (x + Win + I) and type: "Stop-Process -Id idNumber".
I recently ran into the issue when deploying to Service Fabric. The error is implying a 'file' is in use, however, I found that the port was being used by another IDE. By stopping a running service which was already hosting on the port, I was able to stop this exception from occurring.
I've been working on a simple project that uses some common .NET classes, isolated storage, some resources and no external libraries.
Somehow the EXE generated (either in debug or release mode) no longer runs (stops working as soon as it's opened) without giving any details or displaying any exceptions.
It runs normally in visual studio, and there's a .application in the same folder that when clicked starts in install process.
I'm not interested in installation files, I just want it to be the way it was: running an EXE (it's easier to get testers when all you have to do is running it).
I have previous versions of the program, and all of them run normally through the EXE's.
I don't recall changing anything regarding framework, deployment or build. I revised it and there's nothing changed apart from using new objects from the .NET framework.
--[Update]--
Just checked the event viewer. Event data "not available" and answer "not available".
This is a classic example of when a personal version control system would have helped. It would have automatically kept every version of your code including the one right before you made the change that messed up your exe.
Anyway to fix your issue comment out the majority of the code untill it atleast runs. Add a simple output statement just to make sure it is doing something. Then slowly add back in more code.
I suggest you to run your exe file in a consol (cmd.exe) to see if your application displays errors or exceptions in it.
Check the <YourAppName>.Exe.Config file.
Probably it is not well-formed Xml.
I'd start with removing the setup project from the solution, rebuilding then run it in debug mode.
I'm updating an old mobile device application for better flexibility. I had basically added the ability to configure the address of our SQL server in the case that we want to use our test server as opposed to our production server. I don't think this is causing the problem, but I wanted to state it. I also upgraded the project from a VS 2003 project to a VS 2005 project.
The issue I am having is that when I try to run the program in the VS emulator for Pocket PC, I get an error. It occurs after our "main menu" form loads and the user selects the next form to load. The form is initialized without issue, but when we try to run the .ShowDialog() method, it throws a System.MissingMethodException.
I don't have a lot of experience with the Compact Framework and really have no idea where to start looking for problems. I stepped the debugger through the entire initializing process for the new form and it ran without issue. But, again, when we come to the ShowDialog call, it throws the error.
Any ideas in where to start looking or known issues would be greatly appreciated.
I'm usually getting MissingMethodException for this reason:
I've got at least two files in my project, for instance an .exe file and a .dll file
I make changes to the .dll file's source code, and recompile
VS says it deploys the new .dll file to the device, but indeed it does not (it keeps the old file)
The .exe starts up fine, but when it starts accessing the .dll file the application throws a MissingMethodException, because it can't find the methods in the old dll file.
Fix: Delete the entire application directory from the device and redeploy.
I should have added this long ago. The answer ended up being that the incorrect version of .NET was installed on the Mobile Device.
A possible issue that can cause this situation is that the DLL is not being updated when deployed. It can be caused by the DLL in question being a dependency for more than one executable.
For example let's say executable A is running on the device and it is dependent on the DLL's method callA. You are trying to debug executable B which is also dependent on the DLL but on the method callB that you just added. When Visual Studio goes to deploy the DLL with callB in it, it is unable to do so because executable A is still using it. Visual Studio does not tell you that it was not successful in deploying the DLL. (Liar VS! ;)
To fix it, kill all the executables that depend on the DLL and then deploy it.
#Felix Alcala - You got an up vote from me. I would add this as a comment to your fix because it is directly related. Alas, I did not have the rep to do so. But, I want this answer to be public because I found it helpful
Start looking in the ShowDialog method itself. The error is slightly misleading - it's not ShowDialog which it can't find, but the JIT compiler is probably trying to compile ShowDialog, and throwing that exception (because ShowDialog is trying to call something it can't find). If ShowDialog is in a different assembly, then there may be something static that can't be initialized, which could similarly cause this - but start out looking in ShowDialog itself.
Because of this, one trick to finding the problem (if it isn't obvisou) is to reduce the code in ShowDialog until you find the line causing the problem. I'd start out commenting ALL the code, to confirm my hypothesis. If you no longer get the exception, try uncommenting about half of the remaining code at a time, etc.
You can get this exception when you try to use a regular WinForm class from a compact project.