ChatGPT解决这个技术问题 Extra ChatGPT

Visual Studio "Could not copy" .... during build

I keep getting this error during the build of my VS2012 C# project

Error   41  Could not copy "obj\Debug\WeinGartner.WeinCad.exe" to
 "bin\Debug\WeinGartner.WeinCad.exe". 
 Exceeded retry count of 10. Failed.    


Error   42  Unable to copy file "obj\Debug\WeinGartner.WeinCad.exe" to
"bin\Debug\WeinGartner.WeinCad.exe". The process cannot access the file
'bin\Debug\WeinGartner.WeinCad.exe' because it is being used by another 
process.    

Now I've figured out that killing the process

Weingartner.WeinCad.vhost.exe

works (sometimes ) but this is getting on my nerves. Any way to stop this happening at all?

My debugger settings are

https://i.stack.imgur.com/wNEu1.png

For me it was caused by manually launched .exe in the Release directory. The problem was that VS cannot copy over an executable that is still running. I'll try to fix it with properly cleaning up resources so the program does not leave hanging after window close button.
There is a good summary of this problem with typical steps to resolve in this question
This was happening for me because Windows Defender decided it no longer liked the .exe from the VS2019 project upon which I am working. Been working on this for weeks with no issue but today, guess a new update didn't like it. Had to exclude my Source folders. Stopped happening.

D
DavidRR

I have encountered similar error messages in Visual Studio 2013.

Mostly, I have found that this situation has occurred when a debug process was halted because of an exception.

When clean+build has not resolved this problem for me, I have had success by doing the following:

Closing Visual Studio

Deleting the bin and obj folders, and

Reopening Visual Studio.

This "bug" has existed since Visual Studio 2003.

Finally, I have also found that I can often overcome this problem by simply renaming the executable file and then deleting it.


Same here, VS2013. Quitting, deleting build artefacts, restarting -> all good.
i have the same issue, but after restarting VS i get one build, and the files get locked again..
This is not a solution, at the best a partial solution. I dont wanna restart VS every 10min. Cleaning the solution works for me, but cleaning it every 10min is also not a solution.
From my experience, VS2013 does this at least 10 times a day for me no matter what machine I am developing on. It's like the bug has gotten worse. Just sayin'
bug still exist in VS 2019.
G
Geoff

In Visual Studio Premium 2013 (Update 3), I solved this with a pre-build one-liner:

(if exist "$(TargetDir)*old.pdb" del "$(TargetDir)*old.pdb") & (if exist "$(TargetDir)*.pdb" ren "$(TargetDir)*.pdb" *.old.pdb)

This gracefully deletes any old PDB files (if it can), then renames anything that's left with a .old.pdb extension. A nice side effect is that if the old PDB is still locked, it just adds another .old piece to the filename, and they all get cleaned up next time you restart Visual Studio and do a build.

For example, build/debug session 1 leaves MyProject.pdb locked.
The next time you build:
MyProject.pdb --> MyProject.old.pdb

Then, build/debug session 2 is started, and both MyProject.pdb and MyProject.old.pdb are still locked:
MyProject.old.pdb --> MyProject.old.old.pdb
MyProject.pdb --> MyProject.old.pdb

Finally, restarting Visual Studio and doing a fresh build will get rid of both of these, and continue the process as usual.


The same in VS2010, VS 2012
Thank you, worked perfectly for me with modifying your example to using exe files instead. I think this might be a bug in the latest VS 2015 CTP as well.
Glad it helped - I still have my pre-build command set up, and it works well enough that I'd forgotten it was there!
I hate having to do this on principal, but it works, so there's that! :) Thanks for sharing this pearl, Geoff!
Latest (2018-03-11) Visual Studio 2017 v15.6.1: still an issue. Debugging, exception, assemblies in the target directory locked. The above solution with *.pdb changed to *.dll still applies.
T
Tobi Obeck

It's because you have closed your application, but it's still running in background.

Temporary solution:

Go to Task Manager (Ctrl + Alt + Esc).

Go to Processes tab and find "YourProjectName.exe".

Check "Show processes from all users" if you can't find your process.

End Process it.

Permanent solution: you have to close your application through coding. Here is the code...

System.Windows.Forms.Application.Exit();

You have to put this code in to the form's closing event in all form. Example:

private void frm_menu_FormClosing(object sender, FormClosingEventArgs e)
{
    System.Windows.Forms.Application.Exit();
}

This was exactly it. Visual Studio had crashed and IIS Express was still running (in my case). All I had to do was open the task bar and right-click the IIS Express icon and exit. Thank you.
This worked for me; I couldn't delete the obj and bin folders as another process was using them. Thankfully Windows 10 actually said what the name of it was; once it was closed in Task Manager the problems went away
On my side it was on the User tab. Also, I found it using the Process Explorer
Logged off server... logged back on... Issue GONE! Thanks for this permanent fix also... My trouble was killing the process over and over while debugging due to issues...
g
gbjbaanb

the .vhost.exe is a debugger process, so it appears that the process being debugged hasn't closed properly. Chances are you have a bug that's keeping it alive and are not stopping the debug process correctly - there are options to detach from the process when you click 'stop debugging' instead of actually killing the debugger so maybe you have that set.

But that's the problem - the file you're trying to copy over is locked (ie still being used) by the OS so its preventing the copy. Ensure that file is free and you'll be able to copy.


I've added my debugger options to the questions. I'm pretty sure it should be killing the process but maybe I don't understand some options.
In Visual Studio 2019, I am getting a similar message, although it now mentions the process in some of the output (not all). It was testhost.x86.exe that I had to kill off via Task Manager. After that it did seem to stop detecting one of the test processes.
p
pat capozzi

I have solved it by killing IISExpress in task manager


W
Woody1193

The problem is that the debugger/builder creates the executable or library that is identified as a threat by the Anti-virus and therefore deleted right before it could be executed.

Preferably you should tweak your Anti-Virus software to not analyse your project folder.

Some ways to do this, ranked from best to worse, are:

Excluding your project folder from the Anti-Virus Excluding pdb files (Not a 100% guaranteed fix) Turning off Real-Time protection (Not Recommended)


Good catch. I forever hate Avast.
Avast was the problem for me too. Disabling the File System Shield was the answer. I tried adding my Visual Studio\Projects folder to the Exclusions but that didn't work.
I have the same problem with Symantec Endpoint protection. Someone in the IT department has ratcheted up the security level pretty high :-) Thanks Pitrs.
I will add, that you can create exception for the obj\Debug directory for convinient use, instead of disabling the AV or one of it's protective tools.
Thanks! I found that it was an MalwareBytes blocking my .exe file.
S
Sreejith Nair

I was able to fix this issue (VS 2010) through supplying following pre build action;

if exist "$(TargetPath).locked" del "$(TargetPath).locked"

if exist "$(TargetPath)" if not exist "$(TargetPath).locked" move "$(TargetPath)" "$(TargetPath).locked"

@luckyluke, In your project properties, there is section where you can add pre-Build script. Copy and past the above script in that designated area and rebuild the project / run your application
u
usefulBee

Quote:

A workaround is to put this in the Pre-build event command line property of the >project (In the build Events tab):

Code Snippet

if exist "$(TargetPath).locked" del "$(TargetPath).locked"

if exist "$(TargetPath)" if not exist "$(TargetPath).locked" move "$(TargetPath)" "$(TargetPath).locked"

X
Xaimaran

Exception

In some cases in Visual Studio when you (Build || Rebuild) on top of running IISExpress you faced with this Exception:

Unable to copy file "obj\Debug\YourProjectName.dll" to bin\YourProjectName.dll". the process cannot access the file 'bin\YourProjectName.dll' because it is being used by another process

Solution

Right click on web project that needs to build. Click on properties. Select Build Events Tab on the left side. In Pre-build events command line paste these 2 line:

tasklist /fi "imagename eq iisexpress.exe" |find ":" > nul if errorlevel 1 taskkill /f /im "iisexpress.exe"

You are good 2 GO!


S
Stefano.net

My 10 cents contribution.

I still have this problem occasionally on VS 2015 Update 2.

I found that switching compilation target solves the problem.

Try this: if you are in DEBUG switch to RELEASE and build, then back to DEBUG. The problem is gone.

Stefano


Yeah! That's it. This is a simple solution to this annoying problem! Totally worked for me. Easy and quick! Thanks alot.
It works for me! Hint: With deactivated Debug>>Options>>Debugging>>General>>"Use Managed Compatibility Mode" the workaround is not required!
The problem still exists in VS2022! Valuable 10cts from Stefano! Thanks! Much quicker for a larger project than closing and re-opening VS, which works also.
A
Akshay Bagi

Follow the below steps

Open Task Manager ( Ctrl + Alt + Delete ) Under Performance tab select select . Click on End Process. Now Build solution.

Above steps resolved error permanently :)


I
Ivan Ferrer Villa

I think I solved it removing the check mark to Break all processes when one process breaks in Debug options (op's first screenshot->second option).
It's been building/running well for a while since I unchecked it.
I'm using MySql NET Connector and DevExpress controls in my project. May be one of them was not disposing connections, bindings, etc. well because of this flag beeing activated.

EDITED: definitely it works! No more 'Unable to copy file' and no more Form designer errors.


None of the other solutions worked for me. This is the only one. I´m using Visual Studio 2017 13.2
This works always. I use VS2013 Community Edition. Here is my Solution with 17 projects: qurancode.com
C
Cary Bondoc

It seems that by change the assembly name of a project fixes the problem.

So instead of this

https://i.stack.imgur.com/Jbgvm.png

I change it to this

https://i.stack.imgur.com/3Thjm.png

Notice that I just changed it from Increment and Recall to Increment_Recall, I just removed the spaces. It is now working fine to me.


J
JackOrJones

Killing the process w3wp.exe (IIS) will often solve this. Generally, you can know the process that has the lock on the file by navigating to the bin folder and trying to delete it. The error message that will pop up, in case another process is using it, will contain the name of the process that needs to be killed.


A
Ashwin J

I faced the same problem on VS 2012 Version 11.0.60610.01 Update 3 on Windows 8

There were no designer windows open and the project was a simple console application.

The removal of the vshost process accessing the file does not work most of the time since the process isn't accessing the file.

The simplest workaround that works and takes the least amount of time is to remove the project from the solution, build another project in the solution and then add the original back.

It's an irritant and waste of time but it's the least expensive of all the other options that I know of.

Hope this helps...


All you have to do is Rebuild All and everything's fine for another 10 tries. Not much of an inconvenience.
@Scott Shaw-Smith Doesn't work for me. And based on some of the other comments I've seen, it doesn't work for others either. In my case uninstalling Avast fixed it.
s
sofsntp

Add in pre-build event of your master project taskkill /f /fi "pid gt 0" /im "YourProcess.vshost.exe"


Do not really like to solve the problem this way, but this worked!
I've found this the simplest working solution for the problem.
G
Gentleman

If none of the answers works, try this simple check. Find for any MSbuild.exe running and holding your project EXE. Kill MSBuild.exe and you should be good to go.


h
hopperpl

I cannot give a solution to prevent this from happening but you can at least RENAME the locked file (windows explorer, or classic command window) and then compile/build. No need to reboot or restart VS201x. With some experience you can add a pre-build script to delete old files or rename then out-of-the-way in case there's a lock.


N
Novpiar Effendi

Open project properties [ menu > project > properties ] Choose "debug" tab Uncheck "Enable the visual studio hosting process" Start debugging [F5] You will receive security warning , just "ok". Lets application running Stop debugging. Check option "Enable the visual studio hosting process" , under debug tab, Now , try to start debugging , you will not see error again

[Work for me]


Why was this at -2? It has worked for me as well. It makes zero sense but hey, if it works, it works.
Is this a permanent solution? ie do you have to do these 8 steps every time?
vs17 does not have the hosting process option
C
Community

See this other answer. Basically, you could have MSBuild.exe processes running in the background consuming resource files. If you have any pre or post build tasks that cause an MSBuild to be kicked off via command line, try adding the "/nr:false" flag to this command. But again, see the previous answer for more specific details.


Snap, i have the same problem in VS2015 update 2 - MSBuild,exe process needs to be killed in TaskManager before I can re-build.
The article link in Josh's answer above suggests using a system environment variable to disable node reuse within Visual Studio and the MSBuild process (MSBUILDDISABLENODEREUSE=1) - this worked for me.
c
chevhfghfghfgh

I finally how fix it. Why we can't continue debug after the first debug because the first debug exe still running. So that, after first debug, you need to go to Task Manager -> Process Tab -> [your project name exe] end the exe process.

it works for me :)


Wow, Thanks man, exactly my problem. As it asks user password for me while running exe, first time it didn't fire. When i try to delete that app in process list and then debug again, it worked flawlessly.
C
Community

@Geoff's (https://stackoverflow.com/a/25251766/3739540) answer is good, but it throws error code 1 on recompile.

Here is what worked for me (2>nul 1>nul on the end + exit 0):

(if exist "$(TargetDir)*old.pdb" del "$(TargetDir)*old.pdb") & (if exist "$(TargetDir)*.pdb" ren "$(TargetDir)*.pdb" *.old.pdb) 2>nul 1>nul
(if exist "$(TargetDir)*old.dll" del "$(TargetDir)*old.dll") & (if exist "$(TargetDir)*.dll" ren "$(TargetDir)*.dll" *.old.dll) 2>nul 1>nul
exit 0

E
Eric Bishard

I have noticed some answers that solved my problem, BUT, just in case anyone is having the same problem I was.

IF YOU ARE RUNNING A CONSOLE APP: BEFORE YOU DO ANYTHING ELSE.

Make sure you have closed out any console windows that may have been opened from a previous build. For instance I was just testing some code in a console application, I didn't realize that the console window from one of the previous times I ran my program was open. During that session I was debugging, the window got pushed to the back and I couldn't see it. Just saying, this could be your problem, so check to make sure that is not the problem.


P
Pompair

If you are debugging T4 templates, then this happens all the time. My solution (before MS fixes this) would be just to kill this process:

Task Manager --> User --> T4VSHostProcess.exe

This process only comes up when you debug a T4 template, not when you run one.


P
Patrick from NDepend team

Here is a script to definitely get rid of this issue:

REM   This script is invoked before compiling an assembly, and if the target file exist, it moves it to a temporary location
REM   The file-move works even if the existing assembly file is currently locked-by/in-use-in any process.
REM   This way we can be sure that the compilation won't end up claiming the assembly cannot be erased!

echo PreBuildEvents 
echo  $(TargetPath) is %1
echo  $(TargetFileName) is %2 
echo  $(TargetDir) is %3   
echo  $(TargetName) is %4

set dir=C:\temp\LockedAssemblies

if not exist %dir% (mkdir %dir%)

REM   delete all assemblies moved not really locked by a process
del "%dir%\*" /q

REM   assembly file (.exe / .dll) - .pdb file and eventually .xml file (documentation) are concerned
REM   use %random% to let coexists several process that hold several versions of locked assemblies
if exist "%1"  move "%1" "%dir%\%2.locked.%random%"
if exist "%3%4.pdb" move "%3%4.pdb" "%dir%\%4.pdb.locked%random%"
if exist "%3%4.xml.locked" del "%dir%\%4.xml.locked%random%"

REM Code with Macros
REM   if exist "$(TargetPath)"  move "$(TargetPath)" "C:\temp\LockedAssemblies\$(TargetFileName).locked.%random%"
REM   if exist "$(TargetDir)$(TargetName).pdb" move "C:\temp\LockedAssemblies\$(TargetName).pdb" "$(TargetDir)$(TargetName).pdb.locked%random%"
REM   if exist "$(TargetDir)$(TargetName).xml.locked" del "C:\temp\LockedAssemblies\$(TargetName).xml.locked%random%"

REM PreBuildEvent code
REM   $(SolutionDir)\BuildProcess\PreBuildEvents.bat  "$(TargetPath)"  "$(TargetFileName)"  "$(TargetDir)"  "$(TargetName)"

REM References:
REM   http://www.hanselman.com/blog/ManagingMultipleConfigurationFileEnvironmentsWithPreBuildEvents.aspx
REM   http://stackoverflow.com/a/2738456/27194
REM   http://stackoverflow.com/a/35800302/27194

The script needs to be invoked from each VS project pre build event.

$(SolutionDir)\BuildProcess\PreBuildEvents.bat  "$(TargetPath)"  "$(TargetFileName)"  "$(TargetDir)"  "$(TargetName)"

https://i.stack.imgur.com/wbL7L.png


M
M.Hassan

You can kill the application by script.

If your application is named myapp.exe, run the next script in the terminal:

taskkill /IM myapp.exe /F

the parameters are:

/IM   application name (imagename)

 /F                     Specifies to forcefully terminate the process(es).

M
Matt

In my case it was Resharper Unit Tests runner (plus NUnit tests, never had such problem with MsTests). After killing the process, was able to rebuild process, without restarting OS or VS2013.

Other test runners, like xUnit can cause the same issue.

What helps then is to check if you can add a Dispose pattern, for example if you're adding a DbFixture and the database contacts isn't disposed properly. That will cause the assembly files being locked even if the tests completed.

Note that you can just add IDisposable interface to your DbFixture and let IntelliSense add the Dispose pattern. Then, dispose the related contained propertys and explicitly assign them to null.

That will help to end the tests in a clean way and unlock related locked files as soon as the tests ended.

Example (DBFixture is used by xUnit tests):

public class DbFixture: IDisposable
{
    private bool disposedValue;
    public ServiceProvider ServiceProvider { get; private set; }
    
    public DbFixture()
    {
        // initializes ServiceProvider
    }
    
    
    protected virtual void Dispose(bool disposing)
    {
        if (!disposedValue)
        {
            if (disposing)
            {
                // dispose managed state (managed objects)
                ServiceProvider.Dispose();
                ServiceProvider = null;
            }

            // TODO: free unmanaged resources (unmanaged objects) and override finalizer
            // TODO: set large fields to null
            disposedValue = true;
        }
    }

    // // TODO: override finalizer only if 'Dispose(bool disposing)' has code to free unmanaged resources
    // ~DbFixture()
    // {
    //     // Do not change this code. Put cleanup code in 'Dispose(bool disposing)' method
    //     Dispose(disposing: false);
    // }

    public void Dispose()
    {
        // Do not change this code. Put cleanup code in 'Dispose(bool disposing)' method
        Dispose(disposing: true);
        GC.SuppressFinalize(this);
    }
}

The same pattern you need for the test class itself - it needs its own Dispose method (as shown for the DbFixture class above):

   public SQL_Tests(ITestOutputHelper output)
    {
        this.Output = output;
        var fixture = new DbFixture(); // NOTE: MS Dependency injection framework didn't initialize when the fixture was a constructor param, hence it is here
        _serviceProvider = fixture.ServiceProvider;
    } // method

So it needs to dispose its local property _serviceProvider in its own Dispose method, because the test class constructor SQL_Tests instanciated it.


Yep, look for JetBrains.Resharper.TaskRunner.*
You had the right idea, I added something from my experience with xUnit because the issue burned me lot of my time and wasn't easy to fix... hope it is helpful.
c
carraua

This question was the first result when looking for the following error:

Could not copy the file "..." because it was not found.

when building in Visual Studio 2013 (Update 3).

Solution: Uninstalling the "Productivity Power Tools" in Visual Studio 2013.

https://connect.microsoft.com/VisualStudio/feedback/details/533411


Getting this error many times on build for inherited project from TFS. Thought this was it! Searched for this in installed programs, and add-ins. Cannot find this power tools application. Where would this hide?
V
Valamas

I didn't realize I still had my debugger attached and was trying to build in the same Visual Studio instance. Once I stopped the debugger I was able to build.


d
dgundersen

Killing the vstest.executionengine.exe process(es) resolves this issue 90% of the time for me. If that doesn't work, then also killing QTAgent32.exe and then deleting the /bin and /obj folders for the project in question works.

This is the most irritating part of my work day. :)