Error on editor Microsoft (R) Visual C# Compiler version 2.9.1.65535 (9d34608e) (Unity 2019.1.9f1)

Hi,

I'm been having this issue for 4 days now. Things go like this:

I have a Unity project that whenever I open it, some errors show up, saying only " Microsoft (R) Visual C# Compiler version 2.9.1.65535 (9d34608e)" When you select the error, nothing more is shown. No data or clue where to fix the issue. 15 of these errors show up. After some searching, I found out that if I remove the packages installed through the package manager, 14 of these errors disappear, but 1 remains.

The thing is, I need all of the packages that I remove, so if I put them back, the 15 errors show again. And even if I delete them, the last one doesn't disappear.

With these errors, I cannot even put "play" or do much on the editor.

Things I have try:

• Deleting the project and download it again.
• Reimport all assets
• Unistall unity and install it again.
• Search for the same error on internet (9d34608e).
• Open a new project with the same Unity version (the errors do appear even in this new project which contains nothing).
• Reinstall java.
• Check Editor log, which displays this:

Mono: successfully reloaded assembly - Completed reload, in 10.610 seconds
[ScriptCompilation] Recompiling all scripts because: Reload of assemblies failed, assemblies are invalid or forced recompiled
Microsoft (R) Visual C# Compiler version 2.9.1.65535 (9d34608e)
Copyright (C) Microsoft Corporation. All rights reserved.
​

And that is pretty much it.

Here is how the error is displayed on the editor (as you can see, it doesn't show anything of what is actually wrong):


Thanks to anyone reading this and willing to help. I'm on a big hole on this issue.

 

Same error here, let me know if you figure out how to fix it

 

Same! Been at this for 2 weeks now. Getting this error also on mac OSX Mojave 10.14.3.

Error is:

Code (CSharp):

1. Microsoft (R) Visual C# Compiler version 2.9.1.65535 (9d34608e)
2. Copyright (C) Microsoft Corporation. All rights reserved.
3.  
4. error CS0009: Metadata file '/Applications/Unity/Hub/Editor/2019.1.14f1/Unity.app/Contents/NetStandard/compat/2.0.0/shims/netstandard/System.Reflection.dll' could not be opened -- Read out of bounds.
5.  

Have tried all of the following but keep getting the same core error:

• completely uninstalled Unity twice and Visual Studio 2019 (+ ensuring have Visual Studio for Mac Tools for Unity Version 2.2.0.0)
  
• fresh installs of 2019.1.14f1 and 2019.2.2f1
  
• fresh projects from templates, 3D, LWRP and from Unity github samples - like AR Foundation
• all combinations of mono/IL2CPP, Scripting Runtime .Net 4.x and 3.5 & Api Compatibility .Net Standard 2.0 and 4.x
• tried renaming folders like suggested https://forum.unity.com/threads/mic...08e-copyright-c-microsoft-corporation.668395/

Problem seems to have come out of nowhere. Nothing works. Unity is effectively bricked. Can someone please help I'm going nuts lol?

 

same error on 2019.2.3f1. Seems to work fine on booting but updating a package (in this case LWRP) causes error. Didn't show it in video but after i added other packages and got more errors of the same.
Anyone know how to resolve?
2019.1 and 2019.2.2f1 both had the error from the start however in 2019.2.3f1 it seems package change dependant.

 

Same for me.
I worked on 2019.2.2f1 with no problem (Windows 10), but suddenly this error started and I can not compile anything anymore, not even on an empty new project.
I did installed VS2019 lately, but it worked.
Perhaps it have something to do with the installation of Spyder for python? seems unrelated, but the installation did warn me about Environment-Variables risky changes.
I uninstalled Unity, and re-installed Unity 2019.2.5f1, as well as 2019.3(beta), as well as re-installed visual studio 2019, nothing helped.

My unity 2018.3.8f1 still works correctly.

 

Hi. I have exactly the same problem and I also recently installed Spyder.

Can someone help me? I really need to keep working, but I can't even build an empty project.

 

Same error over here.

 

2019.11 same problem.

 

After an hour or so, of looking at file permissions, noting that they were fine (read or even read/write), that the file existed, even when Unity said it didn't. I almost gave up. Unity is really making a mess of things with the Hub, in my opinion.

Regardless, I have _a_ solution - though:
1) it really depends on what DLL it was complaining about, but in my case it was from a project over a year old which I tried to open (and Unity automatically converted - but not very well apparently) and
2) this is just based on my trial and error and who knows if it's even close to the right thing to do!

The new version of Unity I used was 2019.2.11f1 Personal Edition and using the Hub 2.1.3.

I did try some other stuff (like removing the Visual Studio Package and reinstalling from Unity), but it seems this was the solution (and one we should not be expected to do as end-user in my oh so humble opinion):

It was complaining about System.Collections.dll in some huge path. I found the file by right clicking on the Unity App (under hub) in the File Manager and said Show Contents. The actual path I have when doing an "Info" is:
/Applications/Unity/Hub/Editor/2019.2.11f1/Unity.app/Contents/MonoBleedingEdge/lib/mono/4.7.1-api/Facades

Anyway, my solution was to steal the whole 4.7.1-api folder from an earlier version (see snap shot below) of Unity (also by using Show Contents in File Manager):


Anyway, I don't understand, and am rather peeved I had to waste so much time. I wanted to share so you would at least have some kind of solution, though this is Unity's problem (or should be) not ours.

For what it's worth, I had to do this with another directory with two other DLL's (each time shutting down Unity and the HUB and restarting to find the new locations). I was just lucky this approach works, I think. FYI, the other directory was somewhere like:/Applications/Unity/Hub/Editor/2019.2.2f1/Unity.app/Contents/NetStandard/compat/2.0.0/shims/netstandard

Same trick. Just replaced all of that netstandard sub-directory ( I recall! )

 

Unfortunately I doubt this will be of much help, but FWIW the only time I've seen this error is when a file makes use of some C# features that Unity (or, presumably, mono) doesn't yet support/ is unable to compile (most obviously C#8 features like switch expressions). Either way, it's a very unhelpful error message.

 

Hi

I'm having the same problem in version 2019.2.11 and don't know what to do to fix it. I've also installed Spyder for python today for another project too and this appeared today. I can't compile any script, and nothing would work. Any help will be appreciated

In my case, it doesn't mention problems with any dlls

 

This error is so annoying, new projects...and old...i cannot seem to fix it and now i cannot do anything in Unity!!!! now what!!!

 

No nothing!

 

I'm getting the error now in 2019.3.0f3 [for Windows 10] even though I deleted and created a new project from scratch. It worked fine last week! I tried reinstalling Visual Studio and Mono. And now tried reinstalling Unity versions and Unity Hub, just in case a register or env variable was messed up. My error message has the Microsoft copyright notice but no more info, no links to dodgy files or scripts or packages that I can delete. So my error is like fam2k but with 2019.3.0f3, and also I never installed Spyder, so that's NOT the cause of this breakage. (It's worse than a bug because I can't even compile or playtest and empty project!!!)

Regarding anycolourulike's idea to step back through packages, I removed ALL of them from the package manager, so now my /Packages folder (next to /Assets) is empty except for the manifest json file: remove this just caused the default packages to reimport. The Error is still here:

    Microsoft (R) Visual C# Compiler version 2.9.1.65535 (9d34608e)

    Copyright (C) Microsoft Corporation. All rights reserved.

That's all it says....

 

so my question is is anyone from micro-soft or unity trying to fix this problem or are we on our oun because it looks like we all have tried the same things and no answers to any of it anyone from micro-soft out there?????

 

On another thread I left the following message which solved it in my case (fun fact I gave up on Unity for a while because it was broken for weeks with this bug, and starting learning to use Unreal, but I had a seemingly unrelated bug with Visual Studio, and deleting a registry key fixed it. Out of curiosity I went back onto a Unity practice project and it works!)

[copied from my message at https://forum.unity.com/threads/err...compiler-version-2-9-1-65535-9d34608e.716471/ ]

 

I am also facing the same issue when I opened my project in Unity2019.3.0f6 editor. Did anyone find a solution to this?

It says,
Microsoft (R) Visual C# Compiler version 2.9.1.65535 (9d34608e)
Copyright (C) Microsoft Corporation. All rights reserved.

error CS1703: Multiple assemblies with equivalent identity have been imported:
'D:\Unity Projects\cricketVR_2019.3_Vive\Assets\Plugins\System.Data.dll' and
'D:\Softwares\Unity\2019.3.0f6\Editor\Data\MonoBleedingEdge\lib\mono\4.7.1-api\System.Data.dll'.
Remove one of the duplicate references.

 

Yes, at the end I found the solution was the one mentioned by @GregoryFenn , but in my case, I needed it to be deleted on the local machine and in the current user to work out.

You will have to open up the registry and delete the following:
- value for "HKEY_LOCAL_MACHINE\Software\Microsoft\Command Processor\AutoRun".
-Same value but on "HKEY_CURRENT_USER", so it's: "HKEY_CURRENT_USER\Software\Microsoft\Command Processor\AutoRun"

If you don't know how to open the registry, press the windows key + R, that will open up the Run command window, and type there "regedit".

Although in your case @petergraham003 you seem to have multiple .dll with the same name, probably just delete the one that is currently on your folder. Search for System.Data.dll and delete it.

 

Thank you so much! This actually solved my issue!

 

thanks . this save my day :3

 

that's work for me......particularly.I have two errors ,now only one of them is fixed

 

and i see someone says that he installed Spyder for python and this might cause the problem,i didn't install Spyder, but i installed tensorflow and anconda.Perhaps this is relative?

 

NOTE TO SELF: Just had to do this "solution" with 2020 beta. I really wish @unity-admin726 could figure this out. I've sent them bug reports (dozens probably now) and no one seems to understand why we're having these issues. At least no one is talking about it. So, yes, Mike Croswell, you should just copy over all the dll's from an older working version. -Mike Croswell (talking to himself apparently!) 3/28/2020

 

I found the solution. just go to
Edit > Preferences > External Tools > External Script Editor and change it from visual studio 2019 to visual studio 2019 (community)
It solved the problem for me.

 

NOne of the proposed solutions have worked for me. If anyone has any other solutions. I will be glad to hear!
1'1

 

After checking the Unity Editor log I found more details:

-----CompilerOutput:-stdout--exitcode: -1073741795--compilationhadfailure: True--outfile: Temp/UnityEngine.UI.dll
Microsoft (R) Visual C# Compiler version 2.9.1.65535 (9d34608e)
Copyright (C) Microsoft Corporation. All rights reserved.

-----CompilerOutput:-stderr----------
-----EndCompilerOutput---------------
- Finished compile Library/ScriptAssemblies/UnityEditor.TestRunner.dll in 3.342126 seconds
- Finished script compilation in 7.040543 seconds
Microsoft (R) Visual C# Compiler version 2.9.1.65535 (9d34608e)
Copyright (C) Microsoft Corporation. All rights reserved.

Any ideas please?

 

Try clicking on the error and see if there's more text. I thought that's all it said to until I checked - there's more and you may need to scroll down.

For me it was a duplicate DLL.

 

I have this EXACT same error and I still haven't been able to figure it out for weeks now

 

@GregoryFenn Thank you. I successfully solved the problem

 

Having the same issue on Mac...Mac don't have a registry though. I have Visual Studio 2019 selected in external tools in Unity. Anyone have pointers?

 

This fixed the issue for me also. I only had the second registry key entry. It was pointing to an old conda installation.