Bundler creates a ? folder in the project's root directory

whenever I run the bundle install command, bundler creates a directory in my projects 开发者_如何学JAVAroot with the name '?'. How can I prevent this from happening?

I'm assuming the ? directory is due to the fact that some path has not been found, but which? And how could I tackle this issue?

Best regards, DBA

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Deleting the .bundle directory and running bundle install again seems to have solved the issue.