Complete Novice - Am I in the Right Place Please?

Hi, thank you for taking the time to look at this, I won't go into too much detail at the moment in case I am not in the right place but my issue is:
Wildlife camera produces AVI files, I was unable to view some of them, error stating "This file isn't playable. That might be because the file type is unsupported, the file extension is incorrect, or the file is corrupt."
Got onto MS support who downloaded me MPC and did some fiddling also for me and I was then able to view the videos.
I was then converting the AVI files to MP4 using the MS Compressor and Trimmer app to share on FB on Insta with no problem.
I have checked for Codec updates and installed - maybe the correct ones I'm not sure?
Compressor and Trimmer app stopped working with my AVI files.
MS support totally unable to help now and I've got in a right pickle with trying to uninstall and reinstall MPC as they suggested.
Now I'm back to zero on another MPC install with my videos not playing back again with that error message above.

I really would be grateful if anyone could help me please or point me in the right direction. It's my hobby posting my wildlife videos and its really getting me down that I just can't do it in a simple way

Thank you ever so much.

Eli

The "Video compressor & Trimmer" from the Windows Store is not an application from Microsoft. I suspect it might not use the codecs that you have installed. It might be limited to using the standard codecs from Windows, or its own internal codecs.

Consider converting your video into a standard format. I recommend Handbrake:
https://handbrake.fr/
Convert into MP4 file format, with H.264 video and AAC audio.

The K-Lite Codec Pack contains a tool called MediaInfo. That can show you details about your AVI file. For example what kind of video it contains. Copy that details here, and I may be able to give more advice.

Hi Admin, thank you very much for your quick reply.

I didn't realise the compressor & trimmer is not an MS application, see I'm a novice.  

I've just reinstalled MPC and the update (correctly this time I think) and have version:

MPC-HC (Nightly, 64-bit)
------------------------

Build information:
   Version:            1.9.13.29 (92ee446c1)
   Compiler:           MSVC v19.26.28806
   Build date:         Jun 23 2021

LAV Filters:
   LAV Splitter:       0.75.1.0
   LAV Video:          0.75.1.0
   LAV Audio:          0.75.1.0
   FFmpeg compiler:    MinGW-w64 GCC 9.3.0

Operating system:
   Name:               Windows NT 10.0 (build 19042)
   Version:            10.0 (64-bit)

Hardware:
   CPU:                Intel(R) Core(TM) i7-7700HQ CPU @ 2.80GHz
   GPU:                Intel(R) HD Graphics 630 (driver version: 27.20.100.9171)

I checked my current videos and they are now playing thank you.
Here is the MediaInfo for one of my AVI files, I hope it makes sense to you.  I will also have a look at Handbrake for the conversion, there are so many tools out there, I've been overwhelmed with it all today!!
General
Complete name                  : C:\Users\Videos\Jul 21 Cam\DSCF0004.AVI
Format                         : AVI
Format/Info                    : Audio Video Interleave
File size                      : 428 MiB
Duration                       : 2 min 0 s
Overall bit rate               : 29.9 Mb/s

Video
ID                             : 0
Format                         : JPEG
Codec ID                       : MJPG
Duration                       : 2 min 0 s
Bit rate                       : 35.5 Mb/s
Width                          : 1 920 pixels
Height                         : 1 080 pixels
Display aspect ratio           : 16:9
Frame rate                     : 30.000 FPS
Color space                    : YUV
Chroma subsampling             : 4:2:2
Bit depth                      : 8 bits
Scan type                      : Progressive
Compression mode               : Lossy
Bits/(Pixel*Frame)             : 0.570
Stream size                    : 507 MiB

Audio
ID                             : 1
Format                         : PCM
Format settings                : Little / Signed
Codec ID                       : 1
Duration                       : 2 min 0 s
Bit rate mode                  : Constant
Bit rate                       : 256 kb/s
Channel(s)                     : 1 channel
Sampling rate                  : 16.0 kHz
Bit depth                      : 16 bits
Stream size                    : 3.66 MiB (1%)
Alignment                      : Aligned on interleaves
Interleave, duration           : 200  ms (6.00 video frames)
Interleave, preload duration   : 200  ms

Thank you so, so much for your time.
Eli x

Update - I tried to download Handbrake but I got a message that it would not download as it could harm my computer.

The file contains MotionJPEG. Handbrake should be able to convert that.

The download warning is a stupid message from Windows that it should for new files that haven't been downloaded very often yet. Click on the "more information" link in the message. Then you will get an option to download anyway.

You can always use Virustotal to scan files that you don't trust:
https://www.virustotal.com/gui/file/6a11ff32517b79a39c28bd969b0f93ac28336d338311c983fee7aac0bfbb84ca/detection

Oh, that's a problem, because they are up to 1 GB.
What I see now, is very strange, too: clicking on such a file for watching it, opens the MPC-HC player but before watching the film (the few files that work!!)  I have to wait around 7 seconds with players surface. Clicking the next file, the same ... (Windows 10)

I tried to deactivate all hardware decoder in tweak tool (LAV video decoder menu and LAV video decoder MPC HC) but same problem.
Perhaps trying to deactivate hardware acceleration?

Thank you again. I've managed to download Handbrake but its needing a .net. framework piece that is not installing. I'll keep at it and see how I go. It's a minefield all of this to just post up some short video clips evry now and then isn't it.
I don't like fiddling with the back end of my laptop and adding too much to it as I use it mainly for photography, the videos are a sideline. Bit scared of losing everything

Kind regards
Eli x