I have a MVC/C# based website. One of the nuget packages being used is a wrapper around PDFium, a non .NET dll. The PDFium dll is included as part of another nuget package and is just a dll that gets copied into the output directory.
The problem I have is that after I have used the website the PDFium dll (ie the non .net one, not the one that is doing the wrapping) seems to get loaded and then locked by IIS. If I then try to do a build in Visual Studio I get an error saying:
Unable to copy file [Full Source Path]. The process cannot access the file [destination path] because it is being used by another process.
A second line in the build error log shows something similar and additionally confirms:
The file is locked by: "IIS Worker Process (28776)"
If I do an iisreset then this will cause that worker process to get killed and thus the copy can happen but I am wondering if there is any kind of better way of doing this. My thought is that all the other DLLs included by nuget packages and similar get copied just fine so maybe there is something a bit more "proper" that can be done to resolve this rather than the slightly heavy handed iisreset approach...
Not sure if any of this will help, but in order to avoid an IISReset, one option is to ensure that the PDFium.DLL being used by IIS is not the one that's copied to your project's target directory during a build. However, if the PDFium.DLL must sit in the same folder as your wrapper assembly (as I suspect it does), then you might not have a good option other than to use IISReset. You could follow advice here (How to restart the IIS Site when re-compiling an asp.net website) to add a pre-build script, saving you from the manual effort.
If the PDFium.DLL doesn't have to be in the same folder as the wrapper and can be registered anywhere on your system, you can try to set that reference's Copy Local property to false so that no copy is attempted. Obviously, this would work only if the wrapper can find the DLL through its registry entry--if it can be registered...
Our builds have been reporting the same error with IIS locking pdfium.dll causing build failure. When I notice it, I use a tool called LockHunter.
When Lockhunter is installed, in file explorer locate the locked file reported by the
error and right-click it.
In the context menu, LockHunter will have added a menu option
"What's locking this file" - select that.
A LockHunter window will appear which reports the file is locked by
w3wp.exe (IIS worker process).
The LockHunter window has an option to unlock the file, select that.
The file is unlocked and then the build works.
When I debug my project, I get following error:
"Unable to copy file "obj\Debug\My Dream.exe" to "bin\Debug\My Dream.exe". The process cannot access the file 'bin\Debug\My Dream.exe' because it is being used by another process."
Using Process Explorer, I see that MyApplication.exe was out but System process still uses it although I stopped debug before.
Whenever I change my code and start debug it is going to happen. If I copy project to USB and debug, it runs OK.
Why? How can I fix this error?
I use Window 7 Professional. With Xp I have never got this error.
Ugh, this is an old problem, something that still pops up in Visual Studio once in a while. It's bitten me a couple of times and I've lost hours restarting and fighting with VS. I'm sure it's been discussed here on SO more than once. It's also been talked about on the MSDN forums. There isn't an actual solution, but there are a couple of workarounds. Start researching here.
What's happening is that VS is acquiring a lock on a file and then not releasing it. Ironically, that lock prevents VS itself from deleting the file so that it can recreate it when you rebuild the application. The only apparent solution is to close and restart VS so that it will release the lock on the file.
My original workaround was opening up the bin/Debug folder and renaming the executable. You can't delete it if it's locked, but you can rename it. So you can just add a number to the end or something, which allows you to keep working without having to close all of your windows and wait for VS to restart. Some people have even automated this using a pre-build event to append a random string to the end of the old output filename. Yes, this is a giant hack, but this problem gets so frustrating and debilitating that you'll do anything.
I've later learned, after a bit more experimentation, that the problem seems to only crop up when you build the project with one of the designers open. So, the solution that has worked for me long term and prevented me from ever dealing with one of those silly errors again is making sure that I always close all designer windows before building a WinForms project. Yes, this too is somewhat inconvenient, but it sure beats the pants off having to restart VS twice an hour or more.
I assume this applies to WPF, too, although I don't use it and haven't personally experienced the problem there.
I also haven't yet tried reproducing it on VS 2012 RC. I don't know if it's been fixed there yet or not. But my experience so far has been that it still manages to pop up even after Microsoft has claimed to have fixed it. It's still there in VS 2010 SP1. I'm not saying their programmers are idiots who don't know what they're doing, of course. I figure there are just multiple causes for the bug and/or that it's very difficult to reproduce reliably in a laboratory. That's the same reason I haven't personally filed any bug reports on it (although I've +1'ed other peoples), because I can't seem to reliably reproduce it, rather like the Abominable Snowman.
<end rant that is directed at no one in particular>
I've had this error crop up on me before, even in Visual Studio 2008. It came back and more prevalent in Visual Studio 2012.
Here is what I do.
Paste this in the troublesome project's pre-build event:
if exist "$(TargetPath).locked" del "$(TargetPath).locked"
if exist "$(TargetPath)" if not exist "$(TargetPath).locked" move "$(TargetPath)" "$(TargetPath).locked"
Computer (right-click) -> manage -> Service & Application -> service -> Enable Application experience
Worked For me!
I had the same issue in Visual Studio 2013. I'm not sure what caused this for my project, but I was able to fix it by cleaning the solution and rebuilding it.
Build > Clean Solution
Build > Rebuild Solution
I understand this is an old question. Unfortunately I was facing the same issue with my .net core 2.0 application in visual studio 2017. So, I thought of sharing the solution which worked for me. Before this solution I had tried the below steps.
Restarted visual studio
Closed all the application
Clean my solution and rebuild
None of the above steps didn't fix the issue.
And then I opened my Task Manager and selected dotnet process and then clicked End task button. Later I opened my Visual Studio and everything was working fine.
At least in my case I've noticed that visual studio 2012 was creating at least two msbuild.exe ghost processes, which did not perish after build. These zombies apparently are causing file locks to appear.
Killing msbuild.exe's is one time solution, it needs to be done per build basis.
But then I've figure out that I could disable parallel build once and for all - went into Tools > Options > Projects and Solutions > Build and Run > "maximum numbers of parallel project builds" - by default it has value of 8, I've switched to 1. Works like charm.
Of course builds are bit slower now, but better safe than sorry.
At least for this particular small project I did not need more than one build thread.
See my answer here if you're having this problem while running unit tests. Answer copied below:
Building upon Sébastien's answer, I added a pre-build step to my test
project to automatically kill any vstest.* executables still
running. The following pre-build command worked for me:
taskkill /f /im vstest.*
exit 0
The exit 0 command is at the end to prevent build failure when there
are no vstest.* executables running.
I solved this problem..
near the debug you see drop down menu with some configuration. Default there was Any CPU. Select x86 and run the program it will work. If x86 not there go to configuration manager and add the x86
Recently I've been in a trouble with Visual Studio 2012 with same error description: "The process cannot access the file because it is being used by another process..."
To fix this first of all you need to understand the application which still use it. I've shutdown all processes like "MSBuild" and "MSBuild host". But this is not enough. If you have installed "Code Contracts" and turned on then it sometimes takes your DLLs for checking and hanging up on this operation.
So, you need to stop all processes of "CCCheck.exe" and that's all.
Finally, to understand that process is using your DLL you always may try to just Delete "obj" folder in your File Manager and this operation will fail, you may see the "Message Window" with description of the hanging operation. Also, as a variant, you can try to use "Sys Internals Suite" application.
Worked for me.
Task Manager -> Name of project -> End task. (i had 3 same processes with my project name);
VS 2013; Win 8;
Make sure that any previous run of the application (for example, start without debugging option) is actually stopped. I was working on a WPF application, started without debugging and had it minimized when I kept getting the error. After closing the application VS behavior got back to normal.
I have been plagued by this issue in Visual Studio 2017. It started about two or three weeks ago, and has severely eaten into my productivity. Clean and Rebulid haven't worked; even restarting my machine doesn't do the job.
One way to deal with the issue is to clean the offending assembly, and to build (as opposed to rebuild) the project you want to run immediately afterwards. This works about 30% of the time.
However, probably the most reliable solution I've found is to open a Developer Command Prompt, and use msbuild directly. I've been doing this for the last three days, and so far the problem hasn't happened once.
In my case was that I have enable "Show All Files".
Visual Studio 2017
Run taskmanager.
Locate netcore and delete it.
You can then delete the file manually or by running Clean.
This is pure speculation, and not an answer.
However, I have been having this problem for a while.
I came after a time to suspect an interaction between VS and my AV precautions.
After some playing, it seems that it may have gone away when I modified my antivirus so that everything under the
C:\Users[username]\AppData\Local\Microsoft\VisualStudio\10.0\ProjectAssemblies
folder was not included in the real-time protection.
It looks as if the build actually writes the DLL here first, then copies it to the final build location.
It could be too late. But, I encountered similar problem and in my case the project had self reference. Hence, deleting it from the References worked like a charm!!!
I've found the quickest way without closing forms or restarting VisualStudio is go to the project's compile page and click "Advanced Compile Options..." button. Then make any change to one of the options (say, changing Generate Debug Info from Full to pdb-only), then click OK.
It works every time and will have to do until MS fixes this bug (I've never had this problem until I switched from VS2012 to VS2013)
Another note, if you can't clean the project or solution, it won't build. The files are definitely locked by VS (not a antivirus problem, at least not in my case)
I tried all these suggestions as well as other suggestions found elsewhere and the only thing that worked for me was restarting my computer. Then I did a clean solution followed by rebuilding. I am using Visual Studio 2013 for reference.
I have run to this same issue, and what I found is there are actually running mulitple Windows form application in the background. It happens when your application has two forms and you close the 2nd form which is not your main form so the application will not totally exited.
I usually run my application
through its exe or
run without debugging
Solution is close the other instance of Windows form application.
This is one way to always close your application instance.
Pre build command
(if exist "$(TargetDir)*old.pdb" del "$(TargetDir)*old.pdb") & (if exist "$(TargetDir)*.pdb" ren "$(TargetDir)*.pdb" *.old.pdb)
Helped
[Solved] Error: Cannot access file bin/Debug/… because it is being used by another process:
I am approaching that you get this error while you was trying to run two windows form one after another such as first loading a form then after sometimes it will automatically disappear and the second form loaded onto the screen.
Basically, you need to close your first form which is running in the background and the main reason behind this error.
To close the first form you have to add these two lines of code in the second form load event handler.
Form1 form = new Form1();
form.Close();
This will solve the error perfectly.
One simple solution is you go to bin\Debug folder, delete all the files in that folder, then rebuild. If it doesn't work, close Visual Studio then go to bin\Debug folder using file explorer, on the left coner, click on File> Open Command Prompt> Open Command Prompt as Administrator > Enter this command "DEL /F /Q /A *" > then rebuild
i found Cody Gray 's answer partially helpful, in that it did direct me to the real source of my problem which some of you may also be experiencing: visual studio's test execution stays open by default and maintains a lock on the files.
To stop that predominantly useless behaviour, follow the instructions from https://connect.microsoft.com/VisualStudio/feedback/details/771994/vstest-executionengine-x86-exe-32-bit-not-closing-vs2012-11-0-50727-1-rtmrel
Uncheck Test menu -> Test Settings -> "Keep Test Execution Engine Running"
My problem was dotnet got hung up and whenever VS would try to make a new dll, or access an old one, the dotnet process would latch onto the dll and stop visual studio from cloning the dll. Solution is just to end all dotnet tasks in task manager(it will only actually remove the dead one, if you are trying to end one and it won't shut down, that means it's working).
Close VisualStudio, ctrl-alt-delete, select Task Manager, find and end all MSBuild processes - VisualStudio basically has a pretty severe bug where it loses control of its debugger and the debugger maintains a lock on the .pdb file in the debug/bin folder. After you end all the MSBuild (debugger) processes, delete the /debug/bin folder and reopen your solution in Visual Studio. You're good to go now. Microsoft needs to fix this crap.
I have opened a separate question regarding VS 2017 that had a similar behavior after one update. The problem seemed to be generated by the antivirus program although.
I have added the bin folder to the antivirus exclude list, restarted the machine and now it seems to work.
I have faced the same issue, but none of the answers above helped me! I just simply closed my Visual Studio 2017 then re-run it, and It worked!
I've tried every answered here and this worked for me
Close your Project.
Stop running tasks in task manager
Restart your pc
Open and build project again
it worked for me.
I got this error because I was running my solution, but not in debug mode. I had forgotten this. I realized it and stopped my solution from running. This cleared up the issue.
Another kludge, ugh, but it's easy and works for me in VS 2013. Click on the project. In the properties panel should be an entry named Project File with a value
(your project name).vbproj
Change the project name - such as adding an -01 to the end. The original .zip file that was locked is still there, but no longer referenced ... so your work can continue. Next time the computer is rebooted, that lock disappears and you can delete the errant file.
Box was sitting on breakpoint last night when I went to bed. This morning there are service updates which shuts down VS. I reopen VS, do some work to prep for debug, then build. Build fails with: error MSB3231: Unable to remove directory "csx\Debug\". Access to the path 'Microsoft.WindowsAzure.Diagnostics.dll' is denied.
VS is running in Admin mode.
Sometimes Azure Emulator doesn't behave as it shoud and keeps running some processes. You can examine this with ProcessExplorer.
In such cases I re-srtart both emulator services, but in your case restart of the Compute emulator should be enough.
In Visual Studio 2013 I was able to fix this same error by unloading the Azure project and then reloading and building, this seemed lot easier than the answers already provided hence the reason I am answering an already answered question
The best solution I have seen to that is to create a “Post Build Event” to remove the read-only attribute:
attrib -R "$(TargetDir)*.*" /S
That should fix the problem
I have this problem constantly. The following has helped me to clear the issue up:
Disable antiviruses
Disable Windows Search
Disable any file-scanning service
Clean the solution.It will resolve the problem.
The problem is usually that another program is holding onto those directories/files. Closing the offending program ought to free up access and let the Azure build tasks run again.
In my case just now, it was Windows Grep. Another possible culprit is IE (see: http://www.dotnetnoob.com/2013/09/the-unable-to-remove-directory.html).
If needed, you should be able to figure out which program it is by using Process Explorer from the Sysinternals suite, which can show you open file handles. From the Process Explorer menu bar, hit "Find" -> "Find Handle or DLL...", enter part of the path that the Azure build's complaining about, and check the resulting list of programs.
Using Visual Studio 2010 beta, when I run my application within the IDE for debugging, it works perfectly the first time. However, after closing the debug session, either by closing the application or clicking the stop debugging button, all subsequent attempts to debug the application fail with:
Error 1 Unable to copy file "obj\Debug\Application.dll"
to
"bin\Debug\Application.dll".
The process cannot access the file
'bin\Debug\Application.dll'
because it is being used by another
process.
Handle.exe from SysInternals does show handles open, but even if I close the handles, the error doesn't go away. Any attempts to delete the file manually result in an "Access Denied" error message.
To fix this, I have to completely restart Visual Studio, afterwhich the Debug session will work once and stop again.
I'm not entirely sure when this started happening, but I'm pretty sure it's fairly recently.
UPDATE: After I force close the handles on Application.dll, I get the following error from VS:
Error 1 Unable to copy file
"obj\Debug\Application.dll"
to
"bin\Debug\Application.dll".
The requested operation cannot be
performed on a file with a user-mapped
section open.
What the heck is a "user-mapped section"??
UPDATE 2: It appears that this problem occurs when I have a Form open in Design view when trying to debug. I'm going to do some more troubleshooting and then post my results.
UPDATE 3: I think I've narrowed it down to a form using a UserControl.
To be honest with you, it sounds like a bug in VS2010. For some reason it isn't closing the open handles when the debugger stops. Killing the VS process automatically closes those handles, allowing you to access the file again. As a work around, you might look at unlocker it's free and works exceptionally well. I know that's not a great answer, but it should be faster than restarting VS. You might to consider sending a bug report too...
Unlocker doesn't work on 64-bit OS, LockHunter does though.
Here is how I solved this problem
*I open the project Properties,
*select the build tab,
*Clear the output path,
*and buid(this will create the dll in the root folder)
*come back to the output path and select browse(browse to the bin directory to either debug/release)and voila!
As per Error: Cannot access file bin/Debug/… because it is being used by another process answer by TarmoPikaro, sometimes Visual Studio creates multiple msbuild.exe ghost processes, which persist after build. These ghost processes seem to be causing file locks.
Solution 1 - Kill ghost MSBuild.exe's
Killing msbuild.exe's is a one time solution, it needs to be done per build basis.
You can kill the processes as follows mrtumnus:
taskkill /f /im MSBuild.exe
Solution 2 - Disable parallel builds in Visual Studio
You can disable parallel build once and for all:
Tools > Options > Projects and Solutions > Build and Run > "maximum numbers of parallel project builds" - by default it has value of 8, switch it to 1.
Of course builds are bit slower now, but mileage may vary depending on your use case.
This is related to
Error: Cannot access file bin/Debug/... because it is being used by another process
I've seen the Windows Indexing Service cause this. Disabling it helped. Virus scanners can also be at fault. Mutliple Application.Close() calls can supposedly cause this, too.
Of course, since it always works the first time, I suppose these are unlikely.
Had the same problem. The following things helped
Closing all design files while debugging
using unlocker
Also my application opens a port. While debugging an exception was thrown and program quit. While ending the program I closed the port. That helped too.
But definitely, bug with VS2010.
I encountered the same problem and in my case I had the file in question open in Visual Studio. Closing all files helped.
I faced the same error and I was stuck in it for many days. Finally resolved the issue.
I was working on a project that had many class libraries added in it. I added the reference of these libraries to my main project and mistakenly added reference to same project to itself. So when I removed self reference, it worked.
I had this issue myself. I had the project properties window open and that apparently creates a file lock. Even after I closed the window the file lock remained and I had to restart VS.
P.S. I'm using VS 2019. Just posting this for anyone having the issue I had and coming to this post.
If you get this error on VS Code;
Click on terminal screen and use "Ctrl + C" for stop running.