Issues transcoding on new Windows installation

[Chapster5]

Hi all!

I installed a fresh install of Jellyfin Server on my Windows computer last night I've never had Jellyfin I'm coming from Plex but don't fancy paying premium on plex for what I want to do.

I've installed Jellyfin and pointed it to my libraries on an External 8TB SSD and it's found and indexed everything and put the meta info in fine. When I click play on either my laptop or phone app (android) on anything doesn't matter if it's a movie or a TV show I just get an error saying

"The client isn't compatible with the media and the server isn't sending a compatible media format"

Now plex plays them all fine so not sure what to do from here I know nothing really about streaming and transcoding. The teanscoder is set to FFMPEG in the settings and I can't change it. I've tried enabling Hardware Acceleration but I have an Intel 4xxx in built graphics card so don't think it likes that either

Any help would be appreciated am I missing soemthing simple. Is there soemthing I haven't installed that I need?

Appreciate the help!

Thank you!