virtualbox.org

hello I have a problem installing VM VirtualBox on a Windows 8.1 pro team is always going fine until today, now I try to open the application and the service starts in the background but the application does not open , I tried to uninstall VM virtualbox back update latest version , system restore , install previous versions , but always the same thing happens , not because I can not open the application have virtual machines created and can not access them , if anyone knows how I can solve my problem would be grateful to him

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