Movie thumbnails/icons & preview pane not working

HI, I'm trialling DOpus 10 x64 on Windows 7x64 and having big problems with movie thumbnails and the preview pane.

I get no thumbnails for AVI, MPG and most other formats. I only get thumbnails for MP4 and some MOVs. In addition, the preview pane will preview ONLY some MKV files and nothing else. All other video formats show as Hex code in the preview pane.

I previously used to get thumbnails for all videos in Windows Explorer too, now most of those are broken also -- I just see icons. Only MP4 files generate a thumbnail in Windows Explorer.

I've read through every thread on this forum pertaining to these issues, especially the "HOW TO: Enable/fix playback of various media formats in Opus" -- and have implemented all the changes suggested to no avail. I have cleaned out my system of all previous codecs and players, and have now simply got this stuff installed:

  • FFDShow : ffdshow_rev3982_20110915_clsid_x64
  • Media Player Home Cinema x64 :

Other things currently set

  • DOpus Movie plugin is enabled
  • DOpus ActiveX plugin is disabled.
  • I reassociated all media formats with Windows Media Player x64

It seems that I can no longer get thumbnail previews of movies nor can I get the Preview Pane working for most formats. This is a crucial feature for me and I could really do with some help getting this stuff to work.

Many thanks

[ul][li]Can you play the files in question using Windows Media Player 64-bit?

C:\Program Files\Windows Media Player\wmplayer.exe

[li]Can you play the files in question using Windows Media Player 32-bit?

C:\Program Files (x86)\Windows Media Player\wmplayer.exe[/li][/ul]

If the files don't play at all, or only play in the 32-bit version and not the 64-bit version, then that should be fixed first as thumbnails usually won't work without it.

Things to try:

[ul][li]Clear and disable the Thumbnail Cache in Opus. (Settings / Preferences / File Display Modes / Thumbnails.) Without doing that you may end up with a working setup where you're seeing thumbnails generated and cached back when things were not working.

[li]Tell Windows Media Player 32-bit to make itself the default handler for the filetypes/extensions in question. That is often enough to make it re-write the filetype registry details and fix whatever was broken by some other piece of software.

(Note that the 32-bit version is usually the default; you mentioned assigning things to the 64-bit version.)

[li]Compare the filetype registry settings on your machine to those on a similar machine (same OS etc.) where things are working.

My FileTypeDiag tool can help here. If you send the output for one of your affected filetypes I can compare it to my machine's settings.

Often it comes down to some stupid program removing the PerceivedType=Video values from the registry. Unfortunately, when it comes to video, there are a lot of stupid programs. :frowning:[/li][/ul]

Thank you very much for the help. Very interesting!

I used that FileDiag tool and only MP4 and MKV seem to have PreceivedType entries.

I want to retry setting file associations back to Windows Media Player (32 bit), but how can I be sure it's doing the right version?
Control Panel -> Programs -> Default Programs doesn't offer a choice of 32 or 64 bit, it just list "Windows Media Player."

Hmmm. I've just looked at the full list of available file extensions in Control Panel, and many of the "normal" video ones are missing? There's no mention of AVI, MPG, WMV etc? I do get most of the others though: MOV, MP4, MKV. But if I view the associaitons that have been set to Windows Media Player, all the missing ones are listed.

This is all highly confusing!

Sorry, I forgot to answer your questions! Yes, all videos play fine in both WMP x86 and WMP x64.

I've attached a dump from FyleTypeDiag for a non working extension, MPG in this case. A quick search for "PerceivedType" shows no match. I do however have "PerceivedType" for MP4 and MKV because I addded them through that reg file you linked to.
mpg.txt (185 KB)

According to that log, your system doesn't have a .MPG filetype at all, so something must've deleted it. (Probably a poorly written uninstaller, or maybe a registry "cleaner" or something.)

(There are still things in different parts of the registry indicating that WMP should be used when a .MPG file is double-clicked, but the main .MPG filetype under HKEY_CLASSES_ROOT is completely missing.)

Here's a few .reg files with the AVI and some of the MPEG filetype details, taken from a vanilla Windows 7 x64 machine. Try double-clicking them to import their settings and see if that fixes things. (2.74 KB)

Awesome! Thank you so much. That fixes AVI and MPG/MPEG. Actually, now MP4 is broken. (well, I get a thumbnail preview, but only Hex code in the preview pane).

Do you have one for WMV also, or can I simply edit one of these reg files and change the refs in it to WMV? They all look fairly similar...

You mentioned a registry cleaner -- I did indeed run Tunep Utils reg cleaner after I uninstalled all my old codecs and players; I guess that messed things up.

I use "K-Lite Mega Codec Pack" for years (actually with Win7 x64) and it works fine with WMP and within DO. (602 Bytes)

Most likely one of those things did something silly, yeah.

I haven't looked at that particular registry cleaner but, in general, the whole concept of registry cleaners is bogus. They have a close to zero chance of making a positive difference and a far higher chance of breaking something because they assumed something could be "cleaned" when it was still needed.

It may have been one of the codec/player uninstallers and not the registry cleaner, though. Who knows. I know that VLC, as good a player as it is, has done (and maybe still does) some really stupid things will filetypes if you tell it to associate itself with them, and maybe other players/codecs are just as bad. (I still install VLC as it's so useful and generally a great piece of software. Just make sure you tell the installer not to take over any of the filetypes.) QuickTime can also do some awful things to the filetypes and ActiveX settings (one of the reasons I'll never install Quicktime or iTunes outside of a virtual machine again).

This is great, thank you so much Leo for your help. I will definitely be purchasing Dopus when my trial is up. Your support has been great and the software more than solves all the flaws in the Windows 7 version of Windows Explorer (what on earth were MS thinking in removing a lot of the good stuff!?)

I used to use DOpus on the Amiga 20 odd years ago, so I feel like I'm coming home :slight_smile:

Two final things:

  1. I still can't get MP4 files to display in the preview pane movie player -- any solutions for that one?
  2. Quicktimes don't play on my system at all anymore. I did have Quicktime Alternate but removed it. What's the best way of getting Quicktime support (you said QT made a mess of things so I'm not too keen on doing that again!)

[quote="gambit37"]I used to use DOpus on the Amiga 20 odd years ago, so I feel like I'm coming home :slight_smile:
Haha, some years ago I tried DO on Windows - thought feeling home too, but deinstalled, too much to configure, used to Explorer. After 1 year later tried again...configuring never ends, but I feel again "home" now :smiley:

[quote="gambit37"]1) I still can't get MP4 files to display in the preview pane movie player -- any solutions for that one?
2) Quicktimes don't play on my system at all anymore. I did have Quicktime Alternate but removed it. What's the best way of getting Quicktime support (you said QT made a mess of things so I'm not too keen on doing that again!)[/quote]

It's possible that your MP4 and/or MOV filetypes are just messed up. Here are the registry settings for both, from a vanilla Win7x64 machine: (1.06 KB)

For both Quicktime and MPEG4 (which are often the same thing these days, though there are areas where the two formats diverge), I just install an MP4 Splitter and the FFDShow codec. (There are links & instructions in Enable/fix playback of various media formats in Opus FAQ.)

That plays most MP4 files and most (new) Quicktime files; for the odd thing that doesn't play, I drop it on an alternative player with built-in codecs. Video software and file-formats are such a gigantic mess that it's futile trying to get every file to play in one program/setup. You can get most things working, and then with files which are encoded wrongly just have VLC and/or GOM around in case one of them can play the file. (And when none of DirectShow, VLC and GOM can play a file in a format that they should all be able to play, I just delete the file. :slight_smile:)

If you install VLC, just be careful not to let it take over any filetypes as it can trash the registry settings that other programs/APIs depend on. (At least, that is my experience from the past. It may have been fixed/improved since then, but I've never trusted it with my filetypes since it trashed them once.)


Litlle off the topic but I suggest using a media player like potplayer english version ... iew&id=230 that only require a few codecs not many at all.

Best Free Media Player reviews ... htm?page=1

Since I have changed over I don't have any issues with codecs and don't have to worry about them breaking window system files up.


Thanks Leo for your continued support. I added the MP4 and MOV filetypes, but these still don't work in the preview pane, I just get Hex.

I think I may do a reinstall of Windows and start again from scratch -- this install is over a year old and probably a bit unstable!

Hi. Thanks for this topic. I can't preview .mkv files in DO11 viewer pane. Do you a .zip files like the ones you sent for .avi, .mp4, ...
Thanks for your help

The FAQ I linked in my previous post in this thread should have all you might need for MKV playback.