Cook fails in empty project after any successful compilation

Cook fails with ‘Unknown Cook Error’ after any successfull C++ compilation even if project is empty(no content at all). Packaging is not possible when this bug appears

To reproduce the issue follow this steps:

  1. Open UE4 editor of 4.18.2 version
  2. Create a new C++ project from Third Person Template
  3. In Editor push ‘Cook Content for Windows’ button. Cook will be successfull
  4. Do not close an Editor(this is important) and go to Visual Studio 2017 Do not touch any code just push → menu → Build → Build Solution or push CTRL+SHIFT+B. Wait until build success
  5. Go back to the Editor and push ‘Cook Content for Windows’ button again and now cook fails.
  6. If you close the editor and reopen it again you should see message “The following modules are missing or built with a different engine version: YourProject.dll. Would you like to rebuild them now?” - the same message when projects just starts with full rebuild after cleaning(when we deleting Binaries, Build, Intermadiate, Save folders, solution and etc)
  7. Then Cook works again.

Thus any time when I try to use ‘compile from editor’ or ‘build command’(CTRL+SHIFT+B) in Visual Studio Cook fails and I need to close and reopen editor for full rebuild. Maybe this is related to Hot Reload functionality, and cook failure is just a side effect

I have the same problem

Hello,

We’ve recently made a switch to a new bug reporting method using a more structured form. Please visit the link below for more details and report the issue using the new Bug Submission Form. Feel free to continue to use this thread for community discussion around the issue.

https://forums.unrealengine.com/unreal-engine/announcements-and-releases/1410408-unreal-engine-bug-submission-form

Thanks