Unity error CSO246

Hi I'm a complete unity noob so have no clue how to fix this problem. I'm getting the error message in console 'error CS0246: The type or namespace name 'UxmlNamespacePrefix' could not be found (are you missing a using directive or an assembly reference?)'. It's probably something stupid, so here is the code:

Code (CSharp):

1.  
2. using System.Collections;
3. using System.Collections.Generic;
4. using UnityEngine;
5.  
6. public class PlayerController : MonoBehaviour
7. {
8.     // Start is called before the first frame update
9.     void Start()
10.     {
11.  
12.     }
13.  
14.     // Update is called once per frame
15.     void Update()
16.     {
17.  
18.         transform.Translate(0, 0, 1);
19.     }
20. }

I have checked and the name of the class and script are the same as I know that brings up a similar error
Honestly have no clue, would be very grateful for any help

 

On line 2, delete

Code (CSharp):

1. [/ICODE]

Not sure what that's doing there

Also, welcome.

 

Sorry that was me messing up the forum code system that wasn't on the code. Should've checked the post! Thanks anyway though

 

No worries. Copy and paste the full error code. Let's see where the error is. I don't think this script is the problem.

 

This has nothing to do with Unity and absolutely nothing to do with the file above. Perhaps you have some stray code from somewhere else in your project? Sometimes the Rider editor is irritating and adds

using

statements in a failed effort to be helpful. I'm told Rider can be disabled from doing this but my experience says otherwise.

 

An outdated UI package can cause this too. I figured the full error message would point to the culprit.

 

Library\PackageCache\com.unity.package-manager-ui@2.0.7\Editor\AssemblyInfo.cs(7,12): error CS0246: The type or namespace name 'UxmlNamespacePrefix' could not be found (are you missing a using directive or an assembly reference?)
This is the full error code, thanks for all the responses!

Just to clarify I tried to attach this script to a game object but it brought up this error in the console. As well as this, i have tried to attach empty scripts to objects and this error has been brought up

After a little digging i think i found the code causing the issue, but don't know what the issue is

Code (CSharp):

1. using System.Runtime.CompilerServices;
2. using UnityEditor.Experimental.UIElements;
3.  
4. [assembly: InternalsVisibleTo("Unity.PackageManagerCaptain.Editor")]
5. [assembly: InternalsVisibleTo("Unity.PackageManagerUI.EditorTests")]
6. #if UNITY_2018_3_OR_NEWER
7. [assembly: UxmlNamespacePrefix("UnityEditor.PackageManager.UI", "upm")]
8. #endif

 

Found this which looks like the exact same problem:

https://answers.unity.com/questions/1677387/why-am-i-getting-this-error-after-importing-a-tuto.html

Those fixes look like a good bet!

 

Thank you so much! This solved the issue