The type or namespace name 'UI' does not exist in the namespace 'UnityEngine' HELP!

So! Literally all I have done that is causing this issue is the following:

Code (CSharp):

1. using UnityEngine;
2. using UnityEngine.UI;
3.  
4. public class GameMode : MonoBehaviour {
5. }

I have only added this using statement to the script, and it is throwing an error.

Code (CSharp):

1. using UnityEngine.UI;

What is going on here, and how do I fix it? This seems like some inherent problem with the engine not being able to fetch the dlls or something.

The error is as follows:

Severity Code Description Project File Line Suppression State
Error CS0234 The type or namespace name 'UI' does not exist in the namespace 'UnityEngine' (are you missing an assembly reference?) VillageClicker.CSharp D:\Games\Unity Games\Casual\VillageClicker\Assets\TavernProject\Scripts\GameMode.cs 2

I would greatly appreciate any helpful advice.

P.S I have already tried Assets -> Reimport All but to no avail.

 

From the solution explorer of your IDE (MonoDevelop/VisualStudio/whatever you use) check the References.
If there's no UnityEngine.UI -> add it (process will differ depending on IDE).

Either way - did you change any settings recently? It should be added by default unless you were importing a project that had it explicitly removed.

Edit: added sample screenshot from MonoDevelop

 

Hey! Thanks for the quick response!

UnityEngine.UI already exists in the References.

 

This issue still has not been resolved. Would appreciate any additional input as to what might help fix this!

 

This is odd. What version of Unity are you using?

 

The project was created in Unity v5.3.2 (I believe) and I just updated to v5.3.4 yesterday.

 

That rules that out. Occasionally we get people who can't find it in 4.5.

Tried turning it off and back on again? Sometimes restarting Unity and VS helps.

 

Yes. Unfortunately no luck! I wonder if something went wrong in the hotfix update. Perhaps I'll try a reinstall of the engine when I get home today.

 

Looks like if I create new projects, those projects work fine with importing the UnityEngine.UI library. Very strange! I suppose I'll just remake the project and pull the files over. Case closed, sort of.

 

I had the same problem, the problem came on my case from the unitys created 'Library' folder, which is at the root of your project. It should be safe to remove without any care but i suggest to make backup before doing so. Unity will just regenerate it when you reopen it (Heavily suggest to close unity before removing this folder).

 

Apparently they replaced UI with UIElements. UnityEngine.UI.Text replace with UnityEngine.UIElements.TextElement and then the error should go away.

 

This post was 3 years ago...and it is still UnityEngine.UI.Text

UIElements is for editor UI.

https://docs.unity3d.com/Manual/UIToolkits.html

 

Remove Library folder from Project and open Project again resolved this issue.

 

Very good advice. If in doubt, delete the library.

 

Obviously anyone coming here reading this should factor in that doing this will trigger a full reimport and new metadata being created for a lot of stuff. Probably not an issue for most, but on a big big project that can be a long time reimporting, so try to make this your last port of call when troubleshooting!

 

Why would you make the thing most likely to resolve the issue the "last port of call" ?

 

For exactly the reason GameDevCouple_I mentioned. In a large project, it can hours to rebuilt the Library folder. Depending on the issue, a quicker solution like this might be preferable.

 

Here's what worked for me:

Note that removing the Library folder permanently (as someone else suggested) will remove all objects from your scene. But using this method will save them:

So..

1. Close Unity and any code editors you have open
2. Make a backup of the Library folder from your project folder to your desktop
3. Delete the Library folder from your project folder
4. Open your project (Unity will rebuild the Library folder)
5. Close Unity
6. Delete the newly generated Library folder
7. Move the Library folder (you backed up earlier) from your desktop back into your project folder
8. Open your project
9. Open one of your scripts
10. UnityEngine.UI should be fine now

Not sure why this works or if it will have any effect on the rest of your project. My project was fairly small and I didn't see any problems afterwards.

Perhaps someone with more knowledge could point out any problems with this method?

 

As weird as this approach is, this helped me fix my problem.
I am working on Linux in Visual Studio Code for what it's worth.

For whatever reason the issue started happening right after I worked some more on the Scene

 

Deleting the Library folder didn't fix it for me.

What worked was just updating the Visual Studio Code Editor package in Package Manager from 1.1.4 to 1.2.0.

 

It worked for me! Thanks!

 

Same here, it worked what gatzkerob suggested.

Edit: nope, after a few seconds the problem got back...

 

After Importing Firebase Analytics package I am getting this error. I can't solve this
Please help me guys

 

Just figured this out for myself.

I started getting this error after importing an Asset from the Asset Store.

Eventually, I noticed that the asset imported a package called PackageManagerUI.

I uninstalled that package and the errors went away.

I'm using Unity version 2019.3.7f1. Perhaps that package is built-in now.

 

I was trying to add an external dll in my assets folder. The original package came with other files other than the .dll such as a .nupkg, for example. Not entirely sure if that was the problem, but adding the .dll file only seemed to be what finally worked.

 

Thanks ! Worked for me after but not immediately. I had to reopen it multiple times... Don't know why.

 

Alright so I had this issue (both Visual Studio 2017 and VSCode) and didn't want to delete the library folder because its a fairly sized project.

I solved it by doing the following (for Unity 2019.2.3f1):

1. Uninstalled the Visual Studio Code Editor Package then upgraded to latest version of it using Window > Package Manager.
2. Switched to Visual Studio Code from Edit > Preferences > External Tools
3. Opened VSCode and switched to output window for OmniSharp. It told me specific .NET framework was missing and needed to install it. I went to the provided link and installed the EXACT version of .NET developer framework.
4. Waited for install to finish, restarted Unity and VSCode.

Everything started working normally.

EDIT: Oh and don't forget to install C# and Unity Debugger addons for VSCode first.

 

Wow I actually was going through these steps thinking how dumb this was and how it won't work (Was at my wits end). Left this page reopened unity and there it was. Had to come back to this page to give you your kudos. Thanks

 

Hello guys, I have this problems in my visual studio code and any solutions did work for me please help me I can't progress in my script

 

i have solve my problem, I have start the project with a version of unity 2017 and I re start the project files with the 2019.3.10f1 and its good

 

You are my hero. This worked flawlessly for me. Thanks so much!!

 

This is a prime argument for source control. I got this problem and spent a few minutes trying to win then thought to myself "Enough of this. Let's take off and nuke the entire site from orbit."

One delete and one get-latest, the problem is fixed.

 

I had "using UnityEditor.UIElements;" on my import list and I deleted this line,now it works.

 

Uninstalling Unity Collaborate from the Package Manager worked for me

 

I was trying to create a Text variable in a script. Turns out i needed to change the import from Unity.UI to UnityEngine.UI.

 

Another suggestion:

I was running into similar problems in Unity 2019.4.9 (MacOS, VSCode). I fixed it like so:

1. go to Unity > Preferences > External Tools
2. check everything in the "Generate .csproj files for" list
3. click "Regenerate project files".
4. restart VSCode

 

Using Unity 2019.4.10 (Ubuntu 18.04, VSCode)

I had the same problem because I moved the project folder to another directory.
I realized that in the Assembly-CSharp.csproj, there were some lines, at the end of the file, that were pointing to the previous location of the project. I changed the path to my current path and now everything works fine.

I guess that what @simonseo suggested, would do exactly that, for my situation.

 

i don't why a warning symbol occurs near the UnityEngine.UI and before many of those things.What should i do to resolve this.

 

I do not have a reference tab. I am on Mac and I have this problem. I need a solution asap.

 

Hi, this was four years ago I had this problem so your case might be a little different. Sounds strange that your IDE doesn't have anywhere it shows your DLLs. If your issue was the same as mine, which was specific to the version of Unity I was testing at the time so it might not be relevant.. Try to create a new Unity Project in the latest official version of Unity (Not beta) and see if the issue persists then. If it works, all I did was pull over all my files from the other project and continue working.

 

this works for me...i had some issues because of previous project where i manually install sdk for android build. Then when i wanted to start a new project this problem occur...i follow this step but uncheck everything except the first three

 

I'm trying to add the UnityEngine.UI reference to my references in VS2019 following (just the VS portion of ) these instructions but it seems like I need to manually search for it in my windows file system. Does anyone know where it's located?

------------------

UPDATE Didn't realize UnityEngine.UI was a package I needed to explicitly download, I downloaded it and now the references are there. Still not recognizing the UnityEngine.UI namespace in my scripts though. Deleting the Library folder did not resolve, neither did checking the "Generate .cs proj files" settings in the External Tools settings menu.

 

Adding my answer in April 2021, Unity version: 2020.3.2f1. I tried a number of things including removing the Unity Collaborate package. What I ended up finding was somehow in Visual Studio (Mac) some code had been added to the end. I'm not sure when or how it happened. It could have been when typing too fast and accidentally selecting some intellicode choice or something that happened when my mouse when on the fritz and I had to replace the batteries, but the following code appeared at the end of the script and bugged it. Removing it fixed everything.
public class Text
{
public string text { get; internal set; }
}

 

hey i'm having the same issue. I was removing CloudOnce Leaderboard and was adding google play games services leaderboard. But after removing cloudOnce, it began to show such errors and there's no reference of UnityEngine.UI in visual studio. Tell me what should I do??
I also tried to do making new project but after closing unity and opening it again, that reacted the same.

 

did you resolve it? and how?

 

Project/Add Reference- Microsoft Visual Studio

DeSelecting and Selecting again {UnityEngine.UI} resolved the problem for me.

 

Thank you for sharing.
I have tried many fixes, but this one really worked for me.

 

Same on VS code.

 

In my case the problem was sold by removing the ExternalDependencyManager folder. The Google.HandlerVersion have conflict with unityui dll.

 

thank you, worked for me, recent install on Mac Pro Unity 2020.3.22f1 VS 8.10.14