Multiple Precompiled Assemblies With the Same Name

I'm getting an error after I imported a package to Unity,

Code (CSharp):

1. Multiple precompiled assemblies with the same name Newtonsoft.Json.dll included or the current platform. Only one assembly with the same name is allowed per platform. (Assets/Plugins/Newtonsoft Json/Runtime/AOT/Newtonsoft.Json.dll)

I looked around for a solution, and people were saying it had to do with Unity Ads(which I don't have) and another solution I found was to delete one of the Newtonsoft.Json.dll files, which, if I delete either or the app fails to build. I don't even know how to get rid of the package that's caused it, nor do I really want to, the issue started after I imported this package,

https://readyplayer.me/

Is there any way to fix this?

Thanks.

Edit: The duplicate(that came with the above Unity package) seems to be coming from D:/VR-Chat/Library/PackageCache/com.unity.nuget.newtonsoft-json@2.0.0/Runtime/Newtonsoft.Json.dll)

I tried deleting this one as well, the whole package, just to see what would happen. It automatically reimports it.

 

Sorry, can anyone help with this, please?

 

Bump

 

As the error says, you have one too many. You need to remove one. Probably you should contact the readyplayer owners and inform them that including this 3rd-party package is in collision with other packages.

If I'm understanding you correctly, the readyplayer is an asset. If it's true, you just need to remove the dll (Assets/Plugins/Newtonsoft Json/Runtime/AOT/Newtonsoft.Json.dll) from that.
Please use caution, backup your project before you delete anything and/or use your version control system!

All in all, the goal is to have only one file per target platform.

 

I tried backing up this file and deleting it, in both packages. Either one causes an error that prevents building, i was able to build just fine before installing this asset...

Yeah sorry, it's a unity package.

 

Can someone please help with this? I had to remove the package, I have no idea how to get it working. My client would really like to use this package.

 

I'm having the same issue

 

https://forum.unity.com/threads/unity-package-manager-error.1144484/#post-7351460
I didn't realize I had posted this question twice, but here's the link to my other post, MaskedMouse helped me solve it. Hope it helps you.

PS, Kinda rude to just be like "I'm having the same issue" lol

 

Please help me how to resolve this problem,
Multiple precompiled assemblies with the same name Newtonsoft.Json.dll included or the current platform. Only one assembly with the same name is allowed per platform. (C:/Users/GAMEPLAY/Desktop/Train In Jungle/Library/PackageCache/com.unity.nuget.newtonsoft-json@2.0.0/Runtime/Newtonsoft.Json.dll)

 

hi there, i dont know if this solution will help you but it helped me, i rename one of the dlls that was causing me problems in one of the paths, something such as Newtonsoft_old.Json.dll

so unity only took 1 dll, hope it helps.

 

No it's not mate, he's just saying that he too is facing the same problem. It's validation that the problem steps beyond just you that's facing it...

 

It's rude in my opinion to hijack a thread over a month after it was posted and say "I'm having the same problem" without any further explanation, like look at the next guy's question, at least he asked nicely. Btw, why necro my post from 4 months ago just to call me out for calling the guy rude? XD

 

> eh. it's the unity forums - time is a flat circle here.

 

Multiple precompiled assemblies with the same name Newtonsoft.Json.dll included on the current platform. Only one assembly with the same name is allowed per platform. (Assets/UnityPackages/JsonNet/Newtonsoft.Json.dll)

On quixel Unity plugin, any help?

 

I believe Newtonsoft.json.dll is now included in Unity, like version 2020.3.24f1 LTS, it's broken a lot of peoples projects due to already being present. So much for the "LTS" logo meaning

More on this here: Newtonsoft Json package | Page 2 - Unity Forum

 

Hello i have the same problem, i tried deleting the Newton package but it keeps coming back by itself and keeps giving the same error message and i have to go into safemode.

 

I'm having the same issue

 

You can do it, bro. I believe in you.

 

Well in project there was another file in the "Plugin" folder I deleted that Newtonsoft.json.dll file and the error disappeared.

Hope it'll solve this issue for you.

 

Yes, you need to delete the two extra Newtonsoft dlls.

 

Hi everyone, I have the same issue but with System.Test.Json.6.0.1. I spent like 5h hours on that and there is still the same problem... I need help please .

 

It looks like you have a lot of packages... I think you'll need to find every extra copy and delete them all...Click on the error, it shows where they are. Backup to Git before deleting them, just in case.

 

This is the correct answer - this is included in Unity 2021. Some 3rd party packages will have it built in (ROS# for me), but Unity does too, so one of them has to go, or you could go on renaming one of them all throughout your project, which is a pain in the butt.

 

seansteezy's post above solved this for me. Thank you!

 

I understand this is an old post, but if i came across this post via google when trying to find the solution, then others will also.

I found that updating 'version control' in the package manager, Unity registry solved this for me.

I found this solution here
https://forum.unity.com/threads/con...onsoft-and-packagemanagers-newtonsoft.843898/

 

Do you know where is the duplicate file. I am facing issues while using ROS# as well

 

My problem is like this "Multiple precompiled assemblies with the same name Newtonsoft.Json.dll included on the current platform( " My project path on the computer "\Library\PackageCache\com.unity.nuget.newtonsoft-json@2.0.0\Runtime\Newtonsoft.Json.dll),
Multiple precompiled assemblies with the same name Newtonsoft.Json.dll included on the current platform( Assets\UnityPackages\Newtonsoft.Json.dll),
may be the same documents"Newtonsoft.Json.dll" in "My project path on the computer "\Library\PackageCache\com.unity.nuget.newtonsoft-json@2.0.0\Runtime" and "Assets\UnityPackages" are in conflicts with each other, then I delete the "Newtonsoft.Json.dll" doucument in the Unity project page then the problem disappeared

 

ok so I also have the same problem of "mutiple assemblies"
I applied this process mentioned here

https://github.com/siemens/ros-sharp/issues/310#issuecomment-628639384

and the delete the Newtonsoft.Json.dll files present in
C:\1_Drive\MY UNITY\<project NAME>\Assets\Plugins\Newtonsoft Json\Runtime\AOT

Hope this help

 

I'm having the same issue

 

just Remove the Build Report

 

I'm having the same issue

 

You have to delete the extra, that's all. Sometimes there' will be two you have to remove.