DoesPackageExist FAILED: 'None' is not a standard unreal filename or a long path name. Reason: Path should start with a '/'

Hi, I’m trying yo build my project but I have this cook error:

PackagingResults: Error: DoesPackageExist: DoesPackageExist FAILED: ‘None’ is not a standard unreal filename or a long path name. Reason: Path should start with a '/'

I don’t know how to fix it, help please!

Thanks

I tried all that but it still doesn’t work

It seems that this issue is caused by either a corrupted asset reference in your project or the Global Default Server Game Mode being set to None. Try the fixes mentioned in the following links and see if any of them work for you:

https://forums.unrealengine.com/development-discussion/blueprint-visual-scripting/91262-leftover-reference-hidden-in-unreal-project-causing-packaging-errors?p=803839#post803839

https://forums.unrealengine.com/development-discussion/blueprint-visual-scripting/1608305-error-packaging-doespackageexist-failed

You can set Global Default Server Game Mode under project settings here:

I tried for more than 3 hours trying to fix this error and I found one of the possible solutions. The problem can be that there is a reference to the blueprint that was deleted, you need to find all left references and remove them. After this you need to press on content and press ‘fix up redirectors’.

It helped in my case.