Hi there, 

Welcome to the Box Community!

I understand that you noticed that your files have disappeared when you upgraded your Box from Personal Pro to Business Plus, I'm happy to help address this.

Please be advised that during an account upgrade process, Files/folders may not be accessible as your account is in transition and this could take up to 24 hours to complete. Once the transition is completed to your new plan, your files and folder will reappear in your Box account and should be accessible to you again.

Let me know if you have any other questions and I will do my best to help!

Regards, 

Thank you! We look forward to your correspondence.

私も石田さんと同じ状態に陥ってサポートを依頼しております。結局何日くらいで解決したか教えていただけますか？

HIROE DAITOKUさん

結局解決しませんでした。バックアップから別でフォルダごと作り直して再構築しました。

データが多すぎるとサポート依頼しても対応してもらえないのかもしれません。