When I try to upload a world to my realm, it stays on verifying your world for a good 10 minutes and then returns an error code (500). If it is important to know it is a vanilla world and I downloaded it from the server system I was using before.
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Thank you for your report!
We're actually already tracking this issue in REALMS-2146, so I've resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature to see if the issue has already been mentioned.
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So will the problem be fixed? The post you linked has been there for a year and there doesnt seem to be anyone posting solutions.
An update: After restarting my game, when I go to upload my world, once it gets to the verifying step it immediately gives the error code: Upload Failed (500)