This article was previously published under Q319991
Retired KB Content Disclaimer
This article was written about products for which Microsoft no longer offers support. Therefore, this article is offered "as is" and will no longer be updated.
After you compile your Web application, you may receive the following error messages in the Microsoft Visual Studio .NET task list:
Could not copy temporary files to the output directory.
The file 'bin\mywebapp.dll' cannot be copied to the run directory. Theprocess cannot access the file because it is being used by another process.
The file 'bin\mywebapp.pdb' cannot be copied to the run directory. Theprocess cannot access the file because it is being used by another process.
Additionally, the ASP.NET worker process (Aspnet_wp.exe) may hold a lock to dynamic-link libraries (DLLs) in the Bin directory.
Typically, this problem occurs because of a trailing backslash at the end of the path that is set for the root Web site. For example:
This causes the mechanism that copies the DLLs from your Bin directory to the Temporary ASP.NET Files folder to fail. When this mechanism fails, the runtime loads the DLL directly from the Bin directory rather than from the Temporary ASP.NET Files folder.
This problem may also occur if any virtual directories with trailing backslashes have child directories that are marked as Web applications.
For more information about whether a trailing backslash causes this problem, see the "More Information" section.
To resolve this problem, obtain the latest service pack for Microsoft .NET Framework. For additional information, click the following article number to view the article in theMicrosoft Knowledge Base:
318836 INFO: How to Obtain the Latest .NET Framework Service Pack
The English version of this fix should have the following file attributes or later:
Date Time Version Size File name -------------------------------------------------------------- 26-Mar-2002 04:35 1.0.3705.213 192,512 Aspnet_isapi.dll 26-Mar-2002 04:30 19,332 Aspnet_perf.ini 26-Mar-2002 04:35 1.0.3705.213 24,576 Aspnet_regiis.exe 26-Mar-2002 04:35 1.0.3705.213 28,672 Aspnet_wp.exe 20-Mar-2002 12:31 8,709 Smartnav.js 20-Mar-2002 12:31 7,003 Smartnavie5.js 26-Mar-2002 13:34 1.0.3705.213 1,183,744 System_web.dll
NOTE: This fix requires Microsoft .NET Framework Service Pack 1.
To resolve this problem in all circumstances, remove the trailing backslash from the path that is set in the Internet Service Manager.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article. This problem was first corrected in Microsoft .NET Framework Service Pack 2 (SP2).
To verify whether a trailing backslash causes this problem, follow these steps:
Add the following code to a Microsoft Active Server Pages (ASP) page that is located in the same directory as your ASP.NET Web application:
View the page in your browser. Notice that the path includes two backslashes (for example, C:\Inetpub\wwwroot\\mywebapp).
The presence of two backslashes indicates that you included a trailing backslash in the path in Microsoft Internet Information Services (IIS). In this case, C:\Inetpub\wwwroot\\mywebapp indicates that you included a trailing backslash in the path of the root web.
NOTE: If you include extended or escapable characters in the physical path (such as # or %), you cannot copy the DLL. In this case, the DLL also fails to load.