What is .AZ! file extension?
File created by Vuze, a cross-platform BitTorrent client; contains data for a file as it is being downloaded (e.g., ".avi.az!" for an .AVI file); used for marking the file as a download in progress, and the ".az!" file extension is removed when the download is complete.
AZ! files are only supported by some versions of Vuze. For supporting versions, you can turn off the use of the ".az!" extension by selecting Tools → Options..., choosing "Files," and unchecking the "Add suffix to incomplete files" option.
NOTE: When Vuze initiates a download, it allocates the entire target file size on disk, even though the file has not yet been downloaded.
You can see a list of software programs here on www.easyfileopener.org that can open this file type so that you don’t need to search for it on the web. You can then open your file with this extension using a software listed below.