Error MSB3027: Could not copy "C:\pagefile.sys" to "bin\roslyn\pagefile.sys". Exceeded retry count of 10. Failed

could not copy objdebug dll
unable to copy referenced script
the file is locked by .net core host
microsoft common currentversion targets could not copy
unable to copy file obj debug netcoreapp3 1
unable to copy file app config to bindebug
could not find file objdebug designtimeresolveassemblyreferencesinput cache
visual studio 2017 unable to copy file

I am consistently getting this error with VS 2013:

Could not copy "C:\pagefile.sys" to "bin\roslyn\pagefile.sys". Exceeded retry count of 10. Failed. Unable to copy file "C:\pagefile.sys" to "bin\roslyn\pagefile.sys". The process cannot access the file

Please help me.


How to solve Error : Could not copy Exceeded retry count of 10 , 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  Concerning error MSB3027 and error MSB3021, please try the following workarounds to fix them: Restart IDE. Delete the bin and obj folders. Check if there are the files set with permissions and then start Administrative tools --> Services --> Application Open the Project Properties page, under


Repeated build fail - MSB3021, MSB3027, hi i have a MVC web application. its name is StartWPTFramework. when i run my program it runs iis express and show my website correctly. Developer Community for Visual Studio Product family. This site uses cookies for analytics, personalized content and ads. By continuing to browse this site, you agree to this use.


I've found a different solution to this error. In my case I had been moving around a project within my solution (I put it in a subfolder). My references to packages (located in %solutionfolder%/packages) in the project file were broken and I fixed them manually.

However, there are two supplement imports that I forgot:

  <Import Project="..\packages\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.1.0.0\build\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.props" Condition="Exists('..\packages\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.1.0.0\build\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.props')" />
  <Import Project="..\packages\Microsoft.Net.Compilers.1.0.0\build\Microsoft.Net.Compilers.props" Condition="Exists('..\packages\Microsoft.Net.Compilers.1.0.0\build\Microsoft.Net.Compilers.props')" />

I first updated the first one from ..\packages to ..\..\packages (lazy as I am). Building the project after that gave me the pagefile.sys error.

Updating the second import (same change: ..\packages to ..\..\packages) solved it for me.

could not able to copy 'obj\debug\ project.exe to bin\debug\project , MSB3027: Could not copy “obj\Debug\netcoreapp3.0\BinaryPack.Unit. That's not all though, the main problem with this is that closing and  Hello! Every second build my UWP project I&#39;ll get same error: C:\\Program Files (x86)\\Microsoft Visual Studio\\2017\\Enterprise\\MSBuild\\15.0\\Bin\\Microsoft


Remove these two lines from .csproj file:

<Import Project="..\packages\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.1.0.0\build\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.props" Condition="Exists('..\packages\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.1.0.0\build\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.props')" />
<Import Project="..\packages\Microsoft.Net.Compilers.1.0.0\build\Microsoft.Net.Compilers.props" Condition="Exists('..\packages\Microsoft.Net.Compilers.1.0.0\build\Microsoft.Net.Compilers.props')" />

could not copy obj debug exe to bin debug exe Visual studio 2015 , it worked for me once. but next time same error occur. how can solve this problem​. Posted 13-May-13 5:16am. Microsoft.Common.CurrentVersion.targets(4187, 5): [MSB3021] Unable to copy file "" to "". The requested operation cannot be performed on a file with a user-mapped section open. I ended up having to kill the process to start the build. I then start the build and get the following error:


Using the Clean Solution/Rebuild Solution steps resolved this issue for me.

error MSB3021: Unable to copy file · Issue #1707 · dotnet/sdk · GitHub, Describe the bug I'm attempting to develop an ASP.NET Core web NET project, it errors: Error MSB3027 Could not copy "obj\Debug warning MSB3026: Could not copy "obj\Debug etcoreapp1.1\src.pdb" to "bin\Debug etcoreapp1.1\src.pdb" fixed in: visual studio 2017 version 15.3 windows 10.0 visual studio 2017 .net web Jeffrey van der Stad reported Mar 08, 2017 at 06:52 PM


Could not copy ASP.NET Core dll, the file is locked by IIS Worker , Error MSB3027 Could not copy "obj\Debug\netcoreapp3.0\Project.Tests.dll" to "​bin\Debug\netcoreapp3.0\Project.Tests.dll". Exceeded retry  It turned out a member of the team created a project referencing another project, using vs2015 and the compiled files + configs were not compatible with vs2017. As mentioned by @MedAnd upgrading your .net core service fabric does the trick, or if you have visual studio 2017, just creating a new project from there and copying the files from the


The file is locked by NET Core Host error, Error 15 Unable to copy file "obj\Debug\DCS-IRR.exe" to "bin\DCS-IRR.exe". The process cannot access the file 'bin\DCS-IRR.exe' because it is being used by  Could not find file 'obj\Release\myWebProject1.dll'. Why does it work from the command line and not through TeamCity? This is a major show stopper for my dev team. We are excited to get automated builds up and running, but this bothers us. Why would TeamCity compile this differently? What gives?


Could not copy obj to bin? : VisualStudio, Could not copy "obj\Debug\StartWPTFramework.dll" to "bin\StartWPTFramework.dll". Exceeded retry count of 10. Failed. Could not copy "D:\MyFIles\PRO\WPT.MVC.CMS\WPT\WPTFrameworkCore\bin\Debug\WPTFrameworkCore.dll" to "bin\WPTFrameworkCore.dll" is there any one knows the problem?