UNetWeaver error: Exception :System.IO.IOException: Sharing violation on path Assembly-CSharp.dll

I'm constantly getting a sharing violation with the assembly-csharp.dll, its definitely related to UNET.

Code (csharp):

1.  
2. UNetWeaver error: Exception :System.IO.IOException: Sharing violation on path D:\UnityProjects\Project Arrow v3\Temp\Assembly-CSharp.dll
3.   at System.IO.FileStream..ctor (System.String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, Boolean anonymous, FileOptions options) [0x00251] in /Users/builduser/buildslave/mono-runtime-and-classlibs/build/mcs/class/corlib/System.IO/FileStream.cs:320
4.   at System.IO.FileStream..ctor (System.String path, FileMode mode, FileAccess access, FileShare share) [0x00000] in <filename unknown>:0
5.   at (wrapper remoting-invoke-with-check) System.IO.FileStream:.ctor (string,System.IO.FileMode,System.IO.FileAccess,System.IO.FileShare)
6.   at Mono.Cecil.ModuleDefinition.GetFileStream (System.String fileName, FileMode mode, FileAccess access, FileShare share) [0x00000] in <filename unknown>:0
7.   at Mono.Cecil.ModuleDefinition.Write (System.String fileName, Mono.Cecil.WriterParameters parameters) [0x00000] in <filename unknown>:0
8.   at Mono.Cecil.AssemblyDefinition.Write (System.String fileName, Mono.Cecil.WriterParameters parameters) [0x00000] in <filename unknown>:0
9.   at Unity.UNetWeaver.Weaver.Weave (System.String assName, IEnumerable`1 dependencies, IAssemblyResolver assemblyResolver, System.String unityEngineDLLPath, System.String unityUNetDLLPath, System.String outputDir) [0x00212] in C:\buildslave\unity\build\Extensions\Networking\Weaver\UNetWeaver.cs:1724
10.   at Unity.UNetWeaver.Weaver.WeaveAssemblies (IEnumerable`1 assemblies, IEnumerable`1 dependencies, IAssemblyResolver assemblyResolver, System.String outputDir, System.String unityEngineDLLPath, System.String unityUNetDLLPath) [0x00062] in C:\buildslave\unity\build\Extensions\Networking\Weaver\UNetWeaver.cs:1748
11. UnityEngine.Debug:LogError(Object)
12. Unity.UNetWeaver.Log:Error(String) (at C:/buildslave/unity/build/Extensions/Networking/Weaver/Program.cs:20)
13. Unity.UNetWeaver.Weaver:WeaveAssemblies(IEnumerable`1, IEnumerable`1, IAssemblyResolver, String, String, String) (at C:/buildslave/unity/build/Extensions/Networking/Weaver/UNetWeaver.cs:1755)
14. Unity.UNetWeaver.Program:Process(String, String, String, String[], String[], IAssemblyResolver, Action`1, Action`1) (at C:/buildslave/unity/build/Extensions/Networking/Weaver/Program.cs:34)
15. UnityEditor.Scripting.Serialization.Weaver:WeaveUnetFromEditor(String, String, String, String, Boolean)
16.  

Often times the only solution is to reboot (restarting unity has no effect, likely because some hidden process is keeping the file open, and I have no idea what one), but its gotten so bad now unity is basically unusable and for a full release patch, this isn't good, I saw this issue back in the beta patch but here it is still. Does anyone know of a work around for this?

 

I'm getting the same error and I agree with the above user, this way the multiplayer system is unusable.
Any good news about it? This is the error I get:

Code (CSharp):

1. UNetWeaver error: Exception :System.IO.IOException: Sharing violation on path C:\Dati\Progetti Unity\TEST_Multiplayer\TEST_01\Temp\Assembly-CSharp.dll
2.   at System.IO.FileStream..ctor (System.String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, Boolean anonymous, FileOptions options) [0x00251] in /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.IO/FileStream.cs:320
3.   at System.IO.FileStream..ctor (System.String path, FileMode mode, FileAccess access, FileShare share) [0x00000] in <filename unknown>:0
4.   at (wrapper remoting-invoke-with-check) System.IO.FileStream:.ctor (string,System.IO.FileMode,System.IO.FileAccess,System.IO.FileShare)
5.   at Mono.Cecil.ModuleDefinition.GetFileStream (System.String fileName, FileMode mode, FileAccess access, FileShare share) [0x00000] in <filename unknown>:0
6.   at Mono.Cecil.ModuleDefinition.Write (System.String fileName, Mono.Cecil.WriterParameters parameters) [0x00000] in <filename unknown>:0
7.   at Mono.Cecil.AssemblyDefinition.Write (System.String fileName, Mono.Cecil.WriterParameters parameters) [0x00000] in <filename unknown>:0
8.   at Unity.UNetWeaver.Weaver.Weave (System.String assName, IEnumerable`1 dependencies, IAssemblyResolver assemblyResolver, System.String unityEngineDLLPath, System.String unityUNetDLLPath, System.String outputDir) [0x00212] in C:\buildslave\unity\build\Extensions\Networking\Weaver\UNetWeaver.cs:1724
9.   at Unity.UNetWeaver.Weaver.WeaveAssemblies (IEnumerable`1 assemblies, IEnumerable`1 dependencies, IAssemblyResolver assemblyResolver, System.String outputDir, System.String unityEngineDLLPath, System.String unityUNetDLLPath) [0x00062] in C:\buildslave\unity\build\Extensions\Networking\Weaver\UNetWeaver.cs:1748
10. UnityEngine.Debug:LogError(Object)
11. Unity.UNetWeaver.Log:Error(String) (at C:/buildslave/unity/build/Extensions/Networking/Weaver/Program.cs:20)
12. Unity.UNetWeaver.Weaver:WeaveAssemblies(IEnumerable`1, IEnumerable`1, IAssemblyResolver, String, String, String) (at C:/buildslave/unity/build/Extensions/Networking/Weaver/UNetWeaver.cs:1755)
13. Unity.UNetWeaver.Program:Process(String, String, String, String[], String[], IAssemblyResolver, Action`1, Action`1) (at C:/buildslave/unity/build/Extensions/Networking/Weaver/Program.cs:34)
14. UnityEditor.Scripting.Serialization.Weaver:WeaveUnetFromEditor(String, String, String, String, Boolean)

 

Any solution to this error? I've been constantly getting this too.

 

i am getting exact the same error, too

 

I'm having problems related to this on my iMac setup. The same project seems to run fine on windows. Def tied to UNetWeaver

 

Same problem here, Unity 2017.2.0f3

 

Same 2020.3.19f1