Computer freezes when opening mkv per boot

Hi, first off, sorry for wall of text. Decided to give as much details as i can. I have searched the forums as well as google in hopes of a fix and while some threads are similar, i could not fix it with their solution or there was no solution at all.

My problem being once per boot if i were to open some mkv file, mpc would come up and my entire computer freezes (cursor not moving, caps and num locks not toggling) for a good 10 seconds-ish and then plays normally for that file and others the rest of the day until it reboots and happens again but only on the FIRST mkv file of the boot. Surprisingly, this doesn't happen on vlc, i could open the file on vlc on first boot and it would not freeze, then proceed to open with mpc hc and it freezes. the thing is, if i liked vlc, i wouldn't be here right now.

Ok, so about a month ago i reformatted and reinstalled my windows 7 home premium 64bit because it felt like there was a lot of junk. After the fresh install, updated windows and all that stuff, installed k-lite mega 11.7 pretty much default settings, had that problem, didnt think much of it then it got really annoying. Updated to 11.8, still persists and now i'm on 11.8.5 standard last night (really didnt need mega) and its still here.

what i've done to test
- the pack is updated obviously
- tried uninstalling and installing kawaii codec pack(KCP) to see if it was codecs. same issue
- tried install the latest(1.7.10) mpc hc alone and the computer STILL freezes

once again, the settings are pretty much default. don't know if this is useful but, the mediainfo for the problem mkvs seems to have a format profile of high10@l5 like from doki subs. mkvs from horriblesubs have high@L3.1 and they dont freeze. I'm clueless about these but these 2 things stood out to me.

At the time of this writing i am at work with about 5 hours ahead of me, i wont be able to provide further information until i get home, sorry about that. Hope you could help, thanks.

oh also, the thumbnails for mkv are suddenly missing the black film bars but are there on mp4s, how do i get them back?

Can you confirm that the problem only occurs if the first file that you play has subtitles?

I have analyzed this exact problem with someone in the past and it turned out the delay happened while loading a font related component of Windows. It is a standard component of Windows (but made by Adobe). I can't remember the filename right now. So the problem is not codec related. The problem occurs very very rarely. I don't know what causes it. Since it happens just once it might be some kind of security tool (like a virus scanner) that takes a long time scanning that specific file. Or verifying the digital signature of the file is delayed somehow by network issues or a firewall.

We figured out where the delay was happening by using ProcessMonitor to log all file and registry activity. You could try that and see if you can find a gap in the timestamps. It has filtering options, so you can log only the activity of MPC-HC.

You should be able to fix the thumbnail problem by clearing the thumbnail cache. You can do that with the Windows Disk Cleanup tool (cleanmgr.exe) or with CCleaner. The film bars may also be missing if the file contains embedded coverart. Codec Tweak Tool > Thumbnails > Options provides an option to disable use of coverart.

It could also be that the fonts are being cached at first use. Do you perhaps have a lot of extra fonts installed? Or a relatively slow harddrive (laptop drives are usually pretty slow)?

I can confirm that it has subtitles, but like i said earlier, for some files like from horriblesubs which also have subtitles, those could run without freezing. So the problem happens rarely eh? yay me...

No, i do not have extra fonts installed. Ever since the format i did not install any extra fonts and i do not have any Adobe software on this computer. after reading this post, i rebooted, turn off my kaspersky and allowed MPC-HC through the firewall and it still froze.
but I did run process manager for mpc-hc after the reboot but i have no idea how to read it, I did save a log file if you want here; https://drive.google.com/file/d/0B1e_vmfIlbXyYUJRWlJ3Ync1ZjA/view?usp=sharing apologies if I did it wrong.

I am using a desktop[harddrive] and at this time i wouldn't call it slow, prior to the format I did use k-lite 11.4 i think, alongside zoom player and mpc-hc as a secondary and it grew on me, so i only installed mpc-hc through k-lite after the reformat. It didnt freeze my computer at that time.

As for the thumbnails, i did as you said, but the film bars are still missing and still only missing from mkvs. Its not a big deal, but i just thought that if i could fix it, i would like to fix it.

Thanks again.

It probably only happens when the file also contains embedded fonts.

Your log looks similar to what I saw before. The problem starts at 17:13:17,13 when the file atmfd.dll is loaded. That is the Adobe file I was talking about earlier. It is a standard component of Windows, it does not come from any Adobe products. The delay is about 15 seconds. During that time the whole contents of the c:\windows\system32\catroot\ folder is being accessed. I am not sure Windows is doing that.

When I researched the issue in the past, I found people with the exact same problem with different appications, such as a web browser when a website uses a custom font.

Start > Run > services.msc

"Windows Font Cache Service" should be set to load automatically.

Windows font cache service is set to load automatically. would it make a difference if i deleted the font cache manually as opposed to using ccleaner?

Also, i don't know if it matters, but as written in the first post, it happens pretty exclusively on high10p and hevc files, granted, i don't have many different files and i do not have a non-subtitled high10p or hevc mkv file, so im unable to test it out. Sorry.

Its funny how i understand what you are talking about but am more confused than ever at the same time. Like why vlc could open it without freezing but mpc-hc does.

ok, weird thing, the freezing is fixed now for some reason.

I ran windows update and updated some netframe stuff and some optional older kb updates and now its not freezing. Using same file, toggling num lock and was working as intended.

Oh well, at least its fixed for now. Thanks for the help! I'm still missing the reel overlays the side of mkv thumbnails though....

I i've already cleared the cache multiple times and disabled the cover art in the tweak tool, but its still missing...

edit: fixed that too!, went into the registry and changed .mkv preceivedtype to video

Good news. Do you have any idea which software might have set the perceivedtype value to audio?

Unfortunately I'm not sure, I believe it happened when i tested it with by installing KCP. KCP turned the thumbnails to the default mpc ones. I don't remember if they have the film reel bars, then when i uninstalled KCP and went back to k-lite, the thumbnails were just missing the bars.

Also, the preceivedtype was not set to audio, it was an empty value

KCP does not include any thumbnail functionality.

Replacing an existing empty value will be added to next version of K-Lite. Currently it only adds missing values.