Copying assembly from 'Temp' to 'Library' failed

Hi, nine of ten recompilations drive me to this Error:

"Copying assembly from 'Temp/Unity.ugui.dll' to 'Library/ScriptAssemblies/Unity.ugui.dll' failed"

Where you can see "Unity.ugui.dll" is just the last one, there a many of them. Unity.PostProcessing, Unity.RunTime, Unity.TextMeshPro... custom and much more others.

I change the folder Security, add an exclusion on Antivírus, remove a lot of packages from Package Manager.

This erros apears in all my projects. Tested in all 2019 Editor's version.

Please Help Me;

 

+1, this is so annoying and appears to be entirely random. The copy can fail for any assembly definition in my project (it seems like the more assembly defs, the more likely you are to encounter this.)

It would be one thing if this error was just ignorable, but it prevents you from entering play-mode or building.

Edit: 2018.4.0f1

 

We had this issue when building Standalone. I found that in our case this was caused by recompilation of scripts happening when we attempted to make a Standalone Build. This happens when you have "Auto Refresh" disabled. Re-enabling fixed this for us.

If you are getting this for regular editor-only script builds, I don't have any advice.

 

Same problem is being discussed here:
https://forum.unity.com/threads/cop...dll-to-library-failed-project-stucked.669616/

 

You mean auto refresh in Preferences - General? I have that option activated and didnt solve the problem

 

Found a solution somewhere that said i have a bitcoin miner and that's screwing things up. Wierdly enough that turned out to be true. Malewarebytes found the miner and problem was resoleved after the quarantine.

 

Checking by Malewarebytes fixed the problem. Solution confirmed.