Unable to upload / replace world on realm

^{5 August 2023 by [Mojang] CornerHard -} 

Hi everyone, I've seen a couple comments asking for an update, so I wanted to make a post about where we're at and what happens next.

We've updated all Bedrock platforms to our new network stack which did make a big improvement in uploads, and most people are currently able to upload fine to their Realms. However, I know that's not much consolation if you're currently having problems, which you probably are if you've searched out this bug.

When you upload a world to a Realm, there are several things that happen, and if you read through the bug reports here, you'll see different players run into issues at different points.

1. After you pick a world to upload, the game compresses it into an MCWorld file on your device. This can be problematic on some consoles and phones, and there are bugs we're trying to track down, but it's can be difficult if we can't reproduce the problem ourselves.
2. Once the game has an MCWorld file of your world, it gets an upload location from Realms and sends the file over the internet to the Realms service. Currently, this process is pretty fragile, and if your internet gets interrupted or there are other issues with the connection between your device and the Realms service, this can fail. The new network stack focused on improving this, but it's still delicate, especially for long uploads of large worlds.
3. After the MCWorld file is fully uploaded, Realms will unpack the file, check for errors, then copy it to the right storage space so your Realm can use it. This part usually works pretty well, but the game doesn't show a progress bar while this is happening, so many players get confused and cancel out of their upload, even though the process is still working! We have some work in progress to always show a progress bar every step of the process, including this last one.

So what's next? We're working on better progress bars and status during uploads so players don't get confused and cancel their uploads early. Farther ahead, we're building "Realms Storage V2" which will allow us to upload files in pieces, more like what happens when you're uploading a file through your web browser. Now that you can do some Realm management on Minecraft.net, we're also looking into allowing players to upload and download worlds directly on the web, which will help in some situations. For the problems players run into in the world compression step, it's trickier as the platforms can be pretty different and have different storage issues.

If you're running into problems currently, my apologies. The most helpful thing is to post info about which platform (e.g. iPhone) you're playing on, what size the world is, how full your device storage is, and what type of internet connection you're using.