www.makemkv.com

I have filled up a couple hard drives with mkv files and I want to zip/compress them as much as possible to try and free up some room before having to purchase a new drive. With the Windows zip function (windows 10) I am able zip smaller mkv files, about a 2GB file of a tv show episode, but when I try to zip a larger file, around 25-30GB file from a Blu-ray movie, it stalls for a while, displaying the generic Windows file transfer box, sometimes the bar moves across and sometimes not at all, and then displays "Output file write error. Your disk could be full." Which it definitely is not, I am writing to a different disk, about 2TB free.

So is there something I'm not aware of that is preventing me from compressing these larger mkv files? Should I try another ZIP program?

Also, I am attempting this rather than compressing and re-encoding with handbrake because I don't still have a bunch of these disks, and I am wary of getting rid of the original mkv file after running it through handbrake and then discovering later that I'm not satisfied with how that copy came out, or the subtitles aren't working correctly and I would have to go back and fiddle with handbrake to make a new copy.

Help would be appreciated.

Once you get a working HandBrake config that you can verify, subsequent encoding using the same config will produce successful results.

These are the options I use. I've had no issues with the output file.

-s 1,2,3,4 -Z Normal -non-anamorphic -f mkv

pretty simple. If you're set on a .zip, perhaps another zipping program would be more successful, expecially one written for x64 platform if that's what you're on.

You cannot use a general purpose compression algorithm like zip on video files cause they are already compressed much more efficiently with video specific codecs like x.264. Only thing left for smaller sizes is to re-encode with quality loss.