Unity Multiplayer Error: Copying assembly from 'Temp/com.unity.multiplayer-hlapi.Runtime.dll' to 'Library/ScriptAssemb

Hello everyone, I tested everything today to fix that error:

Copying assembly from 'Temp/com.unity.multiplayer-hlapi.Runtime.dll' to 'Library/ScriptAssemblies/com.unity.multiplayer-hlapi.Runtime.dll' failed

Mirror asset got me the same error Temp/mirror.dll.

Ive disabled my antivirus, reinstall unity, that error appear when compiling and follow unable to start by play in-editor function.

Please help me, im going to lost hundred of work staff.

Thanks

 

Solution:

1. Download "Mirror" from asset.
2. Replace all classic Networking component of all gameobjects/prefab by Mirror scripts component (networkmanager, networkidentity, networktransform, ....).
3. In visual studio code at right on Solution references, search "hlapi" and remove all hlapi references.
4. Replace all your "using UnityEditor.Networking" and "using UnityEditor.Networking.X" by "using Mirror;"
5.

 

I had the same problem, and tried that solution. No luck... I still get

Copying assembly from 'Temp/Mirror.dll' to 'Library/ScriptAssemblies/Mirror.dll' failed

 

... and it turned out to be Dropbox. I paused syncing, and the problem went away.

Leaving this note in case others encounter the same problem.

 

Copying assembly from 'Temp/Unity.Timeline.dll' to 'Library/ScriptAssemblies/Unity.Timeline.dll' failed

Copying assembly from 'Temp/Unity.TextMeshPro.dll' to 'Library/ScriptAssemblies/Unity.TextMeshPro.dll' failed

and missing package manager
unity V2019.1.0f2

I'm new to unity and before even started to use I encounter these errors, so ...

 

Same problem here.

Copying assembly from 'Temp/com.unity.multiplayer-hlapi.Runtime.dll' to 'Library/ScriptAssemblies/com.unity.multiplayer-hlapi.Runtime.dll' failed

This is while downloading and installing "Post Processing" version 2.1.6 using Package manager in Unity 2019.1.0f2, this error prevents from using "PostProcessLayer"

 

I got the same issue, after i done the TextMeshPro error. I just did the following :
In Unity go to Window -> Package Manager, Find MultiPlayer HLAPI, then delete it, and reinstall.
When i first tried i installed older version (1.0.0), then i uninstalled, and reinstalled the normal version.
After i run the unity project normally and it worked.
Hopefully helped.

 

This worked for me. Thanks.

 

I got the same issue, I just did the following :
In Unity go to Window -> Package Manager, Find MultiPlayer HLAPI, then delete it, and reinstall.
After i run the unity project normally and it worked.
Hopefully helped.

 

I got a complete project in a local git repo and got the same issue (MultiPlayer HLAPI).
Removing / installing ot from package manager did it for me.

 

Works for me as well. Thanks

 

Unhappily in getting this error trying to reinstall SteamVR 2.3.2. after uninstall. Unity wont install 'Steam VR input' under windows. Out of ideas, suggestions?

 

, remove the file
Library/ScriptAssemblies/com.unity.multiplayer-hlapi.Runtime.dll
and now build works again, once only. The file-removal procedure has to be repeated for every build

 

I had the same error occur to me. All i had to do was update the MultiPlayer HLAPI version to the latest and re-import the package I was trying to import. Go to Window --> Package Manager and find MultiPlayer HLAPI. Check the versions and update it to latest (worked in my case)

 

This some problem with my unity 2019.2.0f1, I fixed updating Multiplayer HLAPI 1.0.2 to 1.0.4 from Windows > Manage Packages.

 

I have the same error
Copying assembly from 'Temp/com.unity.multiplayer-hlapi.Runtime.dll' to 'Library/ScriptAssemblies/com.unity.multiplayer-hlapi.Runtime.dll' failed

 

What worked for me was to set Project Settings -> Player -> Api Compatibility Level to .NET 4.x

 

That's ok! Working for me! Thank You...! I only update MultiPlayer HLAPI of 1.0.2 to 1.0.4 version.

 

I just removed it by going to Windows > Package Manager > MultiPlayer HLAPI > Remove and then installing it again. No idea why it works that way. It just does.

 

thanks for

 

For me, I had to delete "Library/ScriptAssemblies/com.unity.multiplayer-hlapi.Runtime.dll", THEN uninstall & reinstall Multiplayer HLAPI from Package Manager. After that, the Build gave me a "Failed to create ScriptAssemblies directory", and after pressing "Try again", it worked and now works normally every time.

 

same

 

Hoping this helps someone. This may be the most frustrating bug I have ever encountered in a development tool.

This issue and variations on it have hard-blocked me, for over a month, from building one particular branch of our app (which required a newer version of Unity) on my own machine. I have been resorting to building it on another engineer's machine, which mysteriously did not experience this issue.

Today I finally figured out the difference between our two machines. He had auto-refresh turned on in the Unity Editor preferences menu. I had it turned off.

I turned it back on and the issue is now fully resolved.

 

I had cleaned solution in Visual studio and built it back. Then just restart unity and voila it's gone

 

Works

 

Yep, pause Dropbox syncing and restart Untiy fixed it for me.

 

Thanks killerpoke. Worked for me.

 

It's Worked For Me thank You

 

Я русский и я столкнулся с этой проблемой тоже. Все выше перечисленные способы не работали. И тут меня озарило, что возможно виноваты русские буквы в пути проекта. И да, это они были виноваты. Возможно кому-то поможет на его языке тоже. Удачи!

I am Russian and I ran into this problem too. All of the above methods did not work. And then it dawned on me that maybe the Russian letters are to blame in the path of the project. And yes, they were to blame. Perhaps someone will help in his language too. Good luck

 

This worked for me, didn't need to delete, just updated to the latest version. (from 1.0.2 to 1.0.4)

 

Had the same problem, migrated from older unity to 2019 and the same error
Copying assembly from 'Temp/com.unity.multiplayer-hlapi.Runtime.dll' to 'Library/ScriptAssemblies/com.unity.multiplayer-hlapi.Runtime.dll' failed
What I did, was find in Project, Packages, Multiplayer HLAPI, right-clicked and clicked reimport and no error

 

ii just updated that packages which resolved my issue....thanks man

 

my God, had a problem with this too in another tool, Unity 2d extras from github. I did not have dropbox by I had OneDrive. I disabled one drive and the dam thing imported corectly into Unity.

Thanks very much for this tip. I would never have come up with such an idea.

 

Helped me too, needed to only restart the project afterwards.