What breaks my video files?

[jaffer]

I was using extension"download youtube videos as MP4"version 1.8.5.1 with my Opera browser on my desktop computer.
HP Compaq 6000 Pro microtower..Intel Core 2 Duo E7500@2.93GHz
4 GB two channel DDR3
With Win7 Professional 64bit SP1..
I have Avast free version installed..
And I have CCleaner,Speccy and Defraggler..Free versions..
The reason why I´m asking this is that it also is related to a problem with videos downloaded from the tpb..
From the tpb the files were fine..Until I moved them to my USB Sticks.
When I plugged those into my TV..The files stopped playing at certain point..
It showed the full duration of the film and the right file size.
The solution used to be using right click and analyzing with Defraggler.
Which usually found 1 fragmented file..Fragmented it,moved to USB checked all contents again.
And after that the files worked fine.
Last time I did the same thing with Defraggler latest version..
VLC player simply stopped before the time ended and WMP gave an error of not being able to play after some time.
I tried to google this kind of behaviour,but I got nothing.
I don´t know what breaks those files when moving to another location.
I also think that Defraggler is not that good anymore(on friends laptop which has win 8.1 fragmentation was 45% on 1TB hard drive..After fragmenting and analyzing again it was 70%?!!)
So any solution or alternative programs for fragmenting would be great help.

[AncientRome]

Are your USB formats NTFS or FAT?
One thing to keep in mind is that read and writing rates for flash drives are usually low.

All of my videos are fragmented too, especially the bigger ones. Defraggler, Smart Defrag and Auslogics report different fragmentation percentages and some don't fully defrag some files either.

It may be good idea to see if you have scheduled optimization /defrag enabled.
Especially should be disabled on SSD drives.

When in Windows Explorer right click on your drive and select properties.
Click the Tools tab and Click Optimize and check to see if they are scheduled or not.

There are other drive optimizations that you can look up and use to see if it decreases the fragmentation rates on your drive. It has been my experience that high fragmentation rates are related to dying hard drives.

[jaffer]

I can use both formats on my Kingstons and Transcends.
Those are USB 2.0 sticks.My Thomson TV itself is quite demandful of transfer speed.
Usually when I had defragged video files on PC the re-check on attached USB showed no fragmentation.

I don´t have SSD drives
I have Hitachi SATA-II about 300GB drive.
I think I have timed fragmenting set off..I have usually Defragged it with Defraggler.
Once a month entire drive(Unless I have moved large amount of data in it often)and I have disconnected internet and Avast.
Because Avast seem to keep about 16GB fragmented if it´s on..

I have runned checkdisk in boot..But I have not saw any warnings(that thing does always take a while and I have no clue where win7 pro keeps the report of it?)

I have wondered if Defraggler lies about smaller files?
If I download smaller files from youtube(Glitch tutorials,music vids etc)or PDF documents(let´s say like from replacementdocs game manuals)
It shows usually 1 fragmented(14576 fragments(just as example))when analyzing the file itself.
Without defrag there was usually messed colors,chopping of parts and Defraggler fixed it..
I don´t know does it analyze the file or the place the file is written on hard drive.

[AncientRome]

Most defragmentation programs have an option to not defrag files over a certain size.
Avast probably has an auto-optimization option, check to see if it is disabled. It could be trying to defragment files as well.

For drive scanning, I recommend using ViVARD, it is part of the Ultimate Boot CD. It's a slow in-depth scan.

I believe Defraggler has an optimization option where it defrags and then move files to different parts of the hard drive.