Error -50 followed by -9836

Really! thats it is it, i'm shocked no one can help? These Apple communities used to be so helpful but i guess as the Mac OS is such a mess these days its difficult to support just like Windows has always been, so many variables.

My MacBook Air since updating to Catalina two days ago has ruined iTunes and replaced it with the crappy terrible Music app where it no longer shows any of my devices so i cannot sync or do anything with my iPhone of iPad.

Thanks Apple for ruining both of my MacBook's in almost one fell swoop.

Ok, so my devices no longer sync with iTunes as it doesn't exist and my devices do not show in Finder as they are now mean to

I've always used Apple products for their simplicity and ease of use, for years they have been getting more and more frustrating and now i'm absolutely fed up, its just one problem after another I actually do not know what to do anymore.

[Edited by Moderator]

Apple were useless, spoke to someone who says that as my Mac is old and out of date its now unsupported despite it working fine until they clearly made some iTunes account changes, amazing help that. Cheers Apple for ruining both my Macs and destroying iTunes which used to be amazing.........after using OSX for 15 years its now got to the point where its an unusable mess like Windows, full of bugs.

And today i now can't even Sync my iPhone X either wirelessly of plugged into the Mac, I literally give up

I mean i now can't ever sync my iPhone X, I literally give up

Thanks but If you read my original description you’ll see the issue is more complex than those basic suggestions. Nothings changed on the Mac, it worked one day then not the next. I’m wondering if Apple have changed the way the Apple account works and this is what’s causing my issue on an old laptop. It’s fully update to date as far as it can go. The last security update was in 2016