Autocomplete doesn't work on newly added C# script

[plazmaberst]

I’m still a beginner and I’m following CodeMonkey’s tutorial

The autocomplete works fine on my other c# scripts that is not newly added.

Here I just created a new c# script but the autocomplete doesn’t work unless I restart the Unity.
Is there a way to fix this without restarting Unity

[DevDunk]

Which unity version?
Which IDE?
Is the IDE’s package installed/setup properly?
In preferences - external tools did you select your code IDE?

[CodeSmile]

Is this VSCode? If so, I would strongly recommend VS Community if you’re a beginner simply because it’s the more widely supported IDE for which you will get the most help on and have the least amount of trouble with.

VSCode support has generally been ripe with issues in the past, and is currently in a transitional period on top of that. Unity has deprecated VSCode support and corresponding package but very recently Microsoft took on development of a Unity integration package for VSCode - this package is currently in preview.

[Kurt-Dekker]

This may help you with intellisense and possibly other Visual Studio integration problems:

Sometimes the fix is as simple as doing Assets → Open C# Project from Unity. Other times it requires more.

Other times it requires you also nuke the userprefs and .vsconfig and other crufty low-value high-hassle files that Visual Studio tends to slowly damage over time, then try the above trick.

Barring all that, move on to other ideas:

Intellisense Not Working with Visual Studio (Fix)

Likely, if you have appeared here to this page you are having the problem I had for the past hour or so. Intellisense is not working in Visual Studio. Well lucky for you, I figured out the solution to fix this issue after searching the entire web. So you don’t have to search the web anymore, I will tell you how I fixed the issue. Step 1: Close Visual Studio Step 2: In Unity, go to Edit < Preferences < External Tools (left part of the Window) Step 3: In External Tools go to the part that sa…

Also, try update the package inside of Unity: Window → Package Manager → Search for Visual Studio Editor → Press the Update button

Depending on flavor and version of Visual Studio, it may also have an installation step that you perform within the actual Visual Studio. This step seems finicky at best and may require multiple openings of VS before it comes up.

Update: The VSCode extension has been deprecated and abandoned:

Update on the Visual Studio Code package

Hi everyone, We want to update you on the state of the Visual Studio Code for Unity package. This plugin was a result of one of our hackweek experiments by a few of our former employees. Unfortunately, it’s never been fully functional and hasn’t received any updates for almost two years, bringing you an unstable coding experience. We want to be open with you about its state so that you know what to expect. The scripting team has huge projects in the works with a significant impact for a major…

Update: the VSCode integration is back… maybe!?

Microsoft previews Unity extension for Visual Studio Code

We are delighted to announce that Visual Studio Code support for Unity is coming back in a new improved form. In June our friends at Microsoft launched the C# dev kit, which gives Visual Studio Code users access to some of the powerful C# tools more familiar to full Visual Studio users. Today, they are opening a preview of the Unity Extension for Visual Studio Code which brings the Unity experience for Visual Studio into Visual Studio Code. The extension supports code editing powered by Roslyn…

There may be a community fork available that is receiving updates.

GitHub - Chizaruu/com.tsk.ide.vscode: Enhance your Unity development workflow with...

Also, this: No suggestions in Vscode

Recently (July 2023) I worked on a Windows11 system that required a Microsoft component to be installed from within Visual Studio before it would work properly with all the OTHER software installed under Unity. I have no documentation on that process as I have only seen it once and it surprised me as well.