The file extension ASF identifies audio / video files.
The ending ASF is derived from Advanced System Format or Former Advanced Streaming Format.
The files may contain audio and / or video streams. Metadata, chapters and subtitles are also supported.
This proprietary format was developed by Microsoft Corporation and is part of the Windows operating system. As the name implies, the format is suitable for streaming. Asf files are therefore often found on the Internet.
Although most ASF files contain WMV or WMA compression encoded data, ASF is not identical to WMV. If the ASF file contains WMA or WMV data, however, the extension can be changed to wma or wmv.
ASF is not limited to these formats. ASF is a container format and the extension therefore makes no statement about the actual content of the file. Like Quicktime, it is extensible and supports many compression formats for video and audio. These can be contained in various combinations.
The file contents can also be protected by DRM. Then you need the appropriate, possibly paid license to view the content.
Most often resolving problems with opening ASF files is very simple. Just install an appropriate program that supports such files. All of the listed programs support ASF files, but may vary in offered function and purpose. Some programs may be capable only of viewing contents of ASF files or offer file conversion options, but may not be capable of editing such files.
It is possible that although a compatible program has been installed on user’s system, it is not used by the system to open it. This may happen because no default application was associated with this type of files. To associate ASF files with given application, select "Open with" from drop-down menu (accessed by right-clicking on the file). Then select from the list the program or application you want to be used to open this type of file. If the VLC media player applications is not on the list, select "Browse" option in order to manually locate the directory where VLC media player has been installed.
Sometimes problems with opening ASF files may not lie with the application itself, but can arise due to other causes, such as: