It's taken a very long time, but you've finally found and downloaded that audio or video file you've been looking for. So it's particularly frustrating that it won't play. At all. But why?
You could try downloading the file again, just in case it was corrupted. Maybe using another media player would help. How about installing a new codec pack? Troubleshooting media problems is tricky, and you could spend hours trying to figure out the problem.
There is a quicker alternative, though. Just open your audio or video file in MediaInfo, and you'll see lots of technical information about it: video and audio stream type, codec, aspect ratio, frames per second, sample rate and more.
If the file is broken - a missing video stream, say - then you'll see that immediately, and won't have to waste time tweaking your own system. And if it's just using a codec that you don't have installed, then you can quickly grab the latest version, and hopefully fix your playback problems right away. (There's even a "go to the web site of this video codec" button, so it's only a single click away.)
As a bonus, MediaInfo also displays file tags: album and track name, performer, composer, publisher, whatever it might contain. And wide support for video and audio formats means it'll work with just about any file type - MKV, OGM, AVI, DivX, WMV, QuickTime, Real, MPEG-1, MPEG-2, MPEG-4, DVD (VOB), OGG, MP3, WAV, RA, AC3, DTS, AAC, M4A, AU, AIFF and more.
Version 17.12 brings (changelog):
+ MediaInfoOnline: https://mediaarea.net/MediaInfoOnline
+ Dolby Vision: detection of Dolby Vision and display of profile for MPEG-TS and MP4 files
+ MPEG-4: Support of external time code tracks (.qtc)
+ JPEG 2000: Support of IMF profiles
+ F523, BDMV: Support of UHD Blu-ray playlist
+ Endianness and Sign report for PCM Matroska tracks
+ MPEG-4: Resolume DXV display
+ MPEG-4: support of file names >64 chars long or non ASCII for referenced files
+ Slight binary size optimizations
+ colour_description: some changes in order to have more readable names (DCI P3, Display P3, sRGB)
x MP4: crash with some HEVC streams with Dolby Vision
x VC-3: frame rate should not be detected as wrong when there are several frames per block
x Matroska: wrong color range info
x Matroska: fix crash with some corrupted files
x MXF: better support of height when there is an incoherence between header and footer
x transfer_characteristics: fix BT.2020 difference between values 14 and 15
x Trace: fix freeze with some files
x Trace: invalid character encoding with some MOV files
x Some memory leak fixes