MediaFire is designed to be used as a File Sharing service. It is not meant to function as a long term backup service for files. Mediafire does not recommend that you upload files for long term storage as they may be subject to deletion if your account is not accessed, or there is not significant sharing activity on your account (i.e. downloads).
For free accounts, there is currently no time limit on how long uploaded files will be stored as long as you access your account (i.e. login to your account) or your files are being accessed (i.e. downloaded) or there is not an issue of warehousing (storing huge amounts of files without significant downloading activity). Every account is different and different accounts may become idle at different times. Four email notifications will be sent out prior to removing files from our servers for account inactivity. If you are a Mediafire customer and your files were deleted due to inactivity, they are deleted from all servers and cannot be retrieved.
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Như vậy bạn phải đảm bảo login tài khoản đều đặn, đừng ngừng hoạt động tài khoản trong một thời (gian) gian dài thì file sẽ không bị xóa bao giờ cả
