[Solved ?] Windows Explorer no longer shows video tags after the recent major Windows 10 update.

Hello everybody.
My Windows 10 Pro (x64) installation just recently went through a major update to the "new" (latest) version.
After that, Windows Explorer no longer shows anything under the video-tag columns.
For example "Video Tracks", "Audio Tracks", "Subtitle Tracks", etc.: they are all empty for any and all of my video files.
I tried re-installing the FULL version of K-Lite Mega (latest one, i.e.: 12.1.0), and I tried some of the fixes that are possible through the Codec Tweak Tool 6.0.6: no luck whatsoever.
I'd greatly appreciate any suggestions and help.
Thanks in advance,
CRAIG

If you know how to use the Windows Registry Editor (regedit.exe) then look at these keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\PropertySystem\PropertyHandlers
This should contain subkeys for .avi .mp4 etcetera

HKEY_CLASSES_ROOT\SystemFileAssociations\.mp4
This should contain values: FullDetails, InfoTip, PreviewDetails, ExtendedTileInfo

Thanks a lot for your help.

1)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\PropertySystem\PropertyHandlers
Yes, there are sub-keys for .mp4 / .mkv / etc.; they look like this:
(default value) - {f81b1b56-7613-4ee4-bc05-1fab5de5c07e}

2)
HKEY_CLASSES_ROOT\SystemFileAssociations\.mkv or .mp4
Yes there are the 4 values you mentioned.

For .mkv "FullDetails" is the following:

"prop:System.PropGroup.Description;System.Title;System.Media.SubTitle;System.PropGroup.Video;System.Media.Duration;System.Video.FrameWidth;System.Video.FrameHeight;System.Video.TotalBitrate;System.Video.FrameRate;*Icaros.VideoTracks;*Icaros.ContentCompression;Icaros.ContainsChapters;System.Media.CreatorApplication;System.Media.DateEncoded;System.PropGroup.Audio;*Icaros.AudioTracks;System.Audio.ChannelCount;System.Audio.SampleRate;Icaros.SubtitleGroup;*Icaros.SubtitleTracks;System.PropGroup.FileSystem;System.ItemNameDisplay;System.ItemType;System.ItemFolderPathDisplay;System.Size;System.DateCreated;System.DateModified;System.FileAttributes;System.OfflineAvailability;System.OfflineStatus;System.SharedWith;System.FileOwner;System.ComputerName"

For .mp4 "FullDetails" is the following:

"prop:System.PropGroup.Description;System.Title;System.Media.SubTitle;System.Rating;System.Keywords;System.Comment;System.PropGroup.Video;System.Media.Duration;System.Video.FrameWidth;System.Video.FrameHeight;System.Video.EncodingBitrate;System.Video.TotalBitrate;System.Video.FrameRate;System.PropGroup.Audio;System.Audio.EncodingBitrate;System.Audio.ChannelCount;System.Audio.SampleRate;System.PropGroup.Media;System.Music.Artist;System.Media.Year;System.Music.Genre;System.PropGroup.Origin;System.Video.Director;System.Media.Producer;System.Media.Writer;System.Media.Publisher;System.Media.ContentDistributor;System.Media.DateEncoded;System.Media.EncodedBy;System.Media.AuthorUrl;System.Media.PromotionUrl;System.Copyright;System.PropGroup.Content;System.ParentalRating;System.ParentalRatingReason;System.Music.Composer;System.Music.Conductor;System.Music.Period;System.Music.Mood;System.Music.PartOfSet;System.Music.InitialKey;System.Music.BeatsPerMinute;System.DRM.IsProtected;System.PropGroup.FileSystem;System.ItemNameDisplay;System.ItemType;System.ItemFolderPathDisplay;System.Size;System.DateCreated;System.DateModified;System.FileAttributes;System.OfflineAvailability;System.OfflineStatus;System.SharedWith;System.FileOwner;System.ComputerName"

So, looking into .mkv "FullDetails", I do see something like:

*Icaros.VideoTracks
*Icaros.AudioTracks
*Icaros.SubtitleTracks

Does that mean that Windows Explorer should indeed display those properties? (It doesn't).
Does the "*" (asterisk) character have anything do with it, perhaps?

Please forgive my ignorance, and thanks in advance for any help: much appreciated!
CRAIG

[ SOLVED (?) ]
I downloaded and installed Icaros 3.0.0 rc4.
Apparently, now everything works as before.
This solves the problems, yes, but... it would have been nice to understand WHY Windows 10 Explore was no longer showing any of the audio-video properties/columns.
Everybody: thank you for your help.
CRAIG

Icaros is included in the codec pack as well. So normally, a re-install should also enable Icaros again. Perhaps a reboot was required.

The value {f81b1b56-7613-4ee4-bc05-1fab5de5c07e} is from the standard propertyhandler of Windows. {0C08E3BB-D10B-4CC9-B1B3-701F5BE9D6EC} is the value for Icaros. The Windows update probably reset things back to the standard value.

I will ask the developer of Icaros what the asterisks does. Maybe it disables the value. Are they gone now?

Yes, I thought as much... Icaros is included in the Codec Pack (Mega), so re-installing K-Lite should have solved the problem. I can't recall whether I rebooted or not. Maybe not, but I certainly did NOT reboot after installing Icaros "standalone", and everything worked right away, so perhaps a reboot wasn't going to do the trick anyway?
The asterisks are still there, but now all the audio/video properties are showing correctly in Windows Explorer, when I unhide the corresponding columns.
Thank you very much for your help.
CRAIG

The installer instructs Explorer do do a refresh, so a reboot is theoretically not needed.

If it ever happens again and re-installing the codec pack doesn't fix it, then please come here again, so we can analyze the cause.

The asterix is to hide properties with an empty value. So that is normal.