Unity won't start - could not establish connection to Unity Package Manager local server process

I recently did a fresh install of Windows 10 on a Dell Precision M2800 laptop on which I’m trying to run Unity. When try to launch, I receive the following error…

“Could not establish a connection with the Unity Package Manager local server process. This is most likely due to a proxy or firewall configuration. Make sure the process [C:/Progam Files/Unity/Editor/Data/Resources/PackageManager/Server/UnityPackageManager.exe] is reachable via HTTP on the IP address”

I’ve looked online for people that have encountered similar issues but nothing much has seemed to work.

Please let me know what I can do.


FYI, if I add the -noUpm parameter when launching Unity, I can get it to open. That feels like a workaround though, and I’d like to launch without that.

Hi, I got the same error, checked on my browser and got an error hence setx UNITY_NOPROXY localhost did not work for me, so I went to my windows defender firewall with advanced security, and turned off the domain ,public and private profiles since I already have Quick Heal on, and my project started working, I suppose there was a conflict between Quick Heal and Windows Defender as both of them were turned on! I hope that helps!