Unity Hub is supposed to be the easy part: open it, pick a project, start working. When it’s stuck on a spinner, says you have no valid license, fails to install an Editor, or opens a project that immediately closes, you can’t do anything. This guide covers the common Unity Hub not opening problems and how to fix them, including where the logs live so you can see what’s actually wrong.
Quick Fixes First
Try these before anything else. They solve a surprising number of cases:
- Fully quit the Hub. Closing the window often leaves it running in the system tray (Windows) or menu bar (macOS). Right-click the tray icon and choose Quit, or end “Unity Hub” processes in Task Manager / Activity Monitor.
- Restart the computer. Clears stuck background processes and pending updates.
- Update the Hub. Download the latest Hub from Unity’s website and install over the top. Old Hub versions can break when Unity’s services change.
- Check your connection. The Hub needs internet for sign-in and licensing. VPNs, corporate proxies and strict firewalls are common blockers.
- Check Unity’s status page. Sometimes it’s an outage on Unity’s side.
Hub Stuck Loading or Blank Window
A blank white window or endless spinner usually means a corrupted local Hub cache or a GPU rendering issue in the Hub’s Electron window.
- Clear Hub data. Quit the Hub, then rename (to keep a backup) the Hub’s data folder: on Windows
%APPDATA%\UnityHub, on macOS~/Library/Application Support/UnityHub. Restart the Hub; it rebuilds the folder. You’ll need to sign in again and re-add projects and installed editors (use “Add” / “Locate”). - Graphics driver. Update your GPU driver. On laptops with two GPUs, a broken driver can stop the Hub’s window drawing.
- Antivirus. Some antivirus tools block the Hub’s helper processes. Check its quarantine and add an exception for the Hub install folder.
- Reinstall. Uninstall the Hub, delete leftover folders above, and reinstall the latest version.
Sign-In Problems
The Hub signs in through your web browser and hands the result back to the Hub. If you sign in on the web page but the Hub never notices:
- Make sure the browser is allowed to open the unityhub:// link when it asks. If you dismissed that prompt, try again and allow it.
- Try a different default browser for the sign-in.
- Check the system clock is correct. Wrong time and date break secure sign-in tokens.
- Sign out from the Hub’s account menu, quit fully, start again, and sign in fresh.
“No Valid Unity Editor License Found”
Every Editor needs a license, including the free Personal license. In current Hub versions:
- Open the Hub and go to Preferences (the gear icon) then Licenses.
- If no license is listed, click Add and choose Get a free personal license (if you qualify) or activate a serial for Pro/Plus.
- If a license is listed but Unity still complains, try Refresh, or return the license and add it again.
Other causes:
- Offline. Licenses need periodic online checks. Connect and refresh.
- Clock wrong. As with sign-in, a wrong system date makes licenses look expired.
- Licensing client. The license is handled by a background licensing client installed with the Hub. Reinstalling the latest Hub reinstalls it.
- Old Editor versions may need a newer Hub to license properly.
Editor Install Fails
When installing an Editor version or a module (Android, iOS, WebGL support) fails:
- Disk space. An Editor plus modules can take 10 to 20 GB, and downloads need extra temporary space. Check both the install drive and the system drive.
- Install location. In Hub Preferences, check the Editor install path. Avoid paths with special characters or locations that need admin rights, and avoid cloud-synced folders like OneDrive.
- Antivirus scanning large downloads can corrupt or block them. Temporarily pause it or add an exception.
- Retry from scratch. Remove the partially installed Editor from the Installs list, delete its folder, and install again.
- Android modules. The Android Build Support module includes the OpenJDK and SDK/NDK tools sub-options. Tick them all unless you manage those yourself. If Android builds then fail, see the Android Gradle build failed guide.
- Manual install. If the Hub keeps failing, download the Editor installer from the Unity download archive, install it, then use Locate in the Hub’s Installs tab to add it.
Not sure which Editor version to install in the first place? The which Unity version guide explains LTS and supported releases.
Project Won’t Open
When you click a project and nothing happens, or the Editor opens and crashes:
- Missing Editor version. The Hub shows a warning icon when the project’s Editor version isn’t installed. Install that version, or choose a different one from the version dropdown (upgrading has risks; back up first).
- Project path. Very long paths, special characters, or a project inside a cloud-synced folder can cause failures. Move it to something like
C:\Projects\MyGame. - Corrupted Library folder. Close Unity, delete the project’s
Libraryfolder, and open again. Unity rebuilds it, which takes a while on large projects. - Safe Mode. If there are compile errors when a project opens, Unity offers Safe Mode. Enter it, fix the scripts, and exit.
- Already open. Unity won’t open the same project twice. Check for a hidden Unity process and end it. A leftover
Temp/UnityLockfileafter a crash can also cause “It looks like another Unity instance is running with this project open”; delete it when no Unity is running.
If you’re opening an old project in Unity 6, read the Unity 6 upgrade guide first.
Where the Logs Are
Logs tell you exactly what failed. On Windows:
- Hub log:
%APPDATA%\UnityHub\logs\ - Editor log:
%LOCALAPPDATA%\Unity\Editor\Editor.log - Licensing client logs: under
%LOCALAPPDATA%\Unity\
On macOS:
- Hub log:
~/Library/Application Support/UnityHub/logs/ - Editor log:
~/Library/Logs/Unity/Editor.log - Licensing logs:
~/Library/Logs/Unity/
Open the newest file and search for “error”. The Hub also has a Troubleshooting section in Preferences or the Help menu, depending on version, with an option to open the logs folder.
💻 Out of disk space again?
Unity Editors, modules and Library folders eat storage quickly. Our guide to budget laptops for Unity points out which models have room to spare.
Troubleshooting
Unity Hub opens then immediately closes
Clear the Hub data folder and reinstall the latest Hub. Check antivirus quarantine.
“No valid Unity Editor license found. Please activate your license.”
Go to Hub Preferences > Licenses, add a free personal license, and make sure you’re online with a correct system clock.
Editor installation failed / validation failed
Free up disk space, change the install path away from cloud folders, pause antivirus and retry.
Project stuck on “Opening project”
Check the Editor log. Often it’s importing a huge Library; let it finish, or delete Library if it’s stuck on the same asset.
Sign-in page completes but the Hub stays signed out
Allow the browser to open the Unity Hub link, or try another browser.
FAQ
Can I use Unity without the Hub?
You can launch an Editor directly, but licensing is handled by the Hub’s licensing client, so the Hub is effectively required.
Is it safe to delete the UnityHub data folder?
Yes. It holds settings and lists, not your projects or Editors. You’ll re-add them afterwards.
Can I install Editors on another drive?
Yes. Change the Editor install location in Hub Preferences before installing.
Does the free license expire?
Personal licenses need periodic online renewal, which the Hub does automatically when you’re signed in and online.
Why does the Hub want admin rights?
Installing to Program Files needs them. Installing Editors to a user folder avoids repeated prompts.
Reader questions
Asked by readers of this article and answered by AI. Behavior can differ between Unity versions, so test in yours.
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