What is a .BAD file?
A .BAD file usually represents a data error, an undelivered message, or a quarantined file. The most common type is an Exchange Badmail File created by Microsoft Exchange Server. These files store email non-delivery reports and metadata about messages that failed to reach their destination.
Other software also uses the .BAD extension for problematic data. Antivirus programs rename malicious .EXE or .ZIP files to prevent execution. Database software, like Apple iTunes, may mark corrupted .SQL files as .BAD. Torrent clients like uTorrent use it for failed backups.
How to open .BAD files?
Because a .BAD file has multiple possible meanings, you must first identify its actual format. viewer.online/bad can analyze .BAD files to identify the exact format and creator software, inspect the file structure, extract readable text, and check whether an online preview is available.
Software and tools
You can open text-based .BAD files using a standard text editor like Notepad++. If the file is a renamed archive, extraction tools like WinRAR might open the contents. You can also try to recover data by renaming the extension back to its original format, such as .JPG, .ZIP, or .DOCX, depending on the source system.
File conversion
Once you know the original format of your data, you can convert the file to sensible target formats on convert.guru. For example, you can convert text-based logs to .TXT or email data to .EML.
Summary
viewer.online/bad is useful for identifying, inspecting, and understanding .BAD files without installing software or dealing with compatibility problems.