: If the file is 0KB or throws an error when opening, it may be a locked temporary file currently in use by a Yamaha background process.

: If you did not download a Vocaloid-related tool recently, be cautious. Malicious files sometimes use obscure names to hide.

To look inside the archive, you will need a utility that supports 7z decompression: : Use 7-Zip (Official/Free) or WinZip .