Alien Worlds: “Cannot read property ‘Symbol(Symbol.asynclterator)’ of undefined” Error

Alien Worlds is a DeFi NFT play-to-earn game on the WAX blockchain, where you can collect and play with unique ERC-20 fungible tokens.

Players enter the metaverse in the role of Explorers, by buying (or earning) NFT packs. Explorers earn through game play and by participation in Planet DAOs. You can farm Trilium and NFTs by mining on planets or by owning land where you charge rental commission.

Alien Worlds was one of the earlier and more successful play-to-earn NFT games, thanks in large to the generous rewards players were getting by mining. A small investment in mining equipment could easily net you $10-30 per day in mining profits and, if you were particularly lucky, some rare NFTs that you could then sell on Atomic Hub for hundreds of dollars.

However, those days are long gone. As in many other play-to-earn games, if people can find a way to exploit the game to make money, they will. And they did.

A big part of the in-game mining today is done by bots. Bots don’t need to sleep, nor eat, or socialize – they are the most effective miners in Alien Worlds and the reason why the game stopped rewarding players with NFTs and considerably lowered the mining rewards. The team behind Alien Worlds admitted earlier this summer that probably a big chunk of the overall mining is done by bots and that the team has no effective way to identify and stop them.

Even so, I continued with the game. I had solid mining tools that could still bring some Trilium and only asked of me a few dozen clicks per day. That is, until the “Cannot read property” error.

Cannot read property

Alien Worlds: Explorer
Alien Worlds: Explorer

I have had the occasional issue with “Cannot read property ‘Symbol(Symbol.asynclterator)’ of undefined” error ever since I first started with the game. However, a quick reload usually fixed it. This issue appears just when you try to log into the Alien Worlds browser app, just as the game goes in to “Fetching player” phase.

This all changed a month back, when a reload would still produce the error. Suddenly it took 10-20 reloads, to finally enter the game. I checked the Internet and found others on Reddit who were plagued by the same error, without solution. It’s just something I got to put up with, I thought.

Also, I realized that if you keep pressing “Enter” while the error is displayed, the game would try to log you in again, so that became a quicker method than just trying to reload.

Then two weeks back, the error would completely block me from the game. Nothing worked and it was finally time to contact support.

I made screenshots of the error with the console visible and even identified the issue to be a “Fetching Player” error, preventing the game to load. Yet, all I got from support was clear cache and browser data, or try another browser.

I tried six browsers, from Chrome to Brave and must have cleared cache and data a hundred times. I could not enter the game. After sharing the results, support stopped responding to my emails.

Not a happy end

I have since left the game because of this error. I sold most of my tools and not looking to come back. Bots couldn’t stop me, but the bugs did, in the end.

If anyone finds a solution for the error, please let me know. I’ll place it in this article, so it can help others.

UPDATE: 28th of August, 2021

I received a new email today from support:

Hi Explorer,
API issues should be less at the moment, please retry after clearing cache/cookies (or try incognito) thank you for your patience!

I tested the game a few times after I received the email and it seemed to work OK, no Log In issues. However, when I tried again later that day, it was the same old error.

Even if I somehow log in after reloading a few times, I would often get a “Failed to Fetch” error when the game tried to connect to the WAX wallet when claiming mining rewards.

Conclusion: The game is still broken for me, and this seems to be an error that they cannot fix. Some days the game will start without an error; other days I get the error, click OK and try to Log In again, this time successfully; different times I need to reload the loading screen 7-8 times to be able to Log In; and then some days it just doesn’t seem to work at all, no matter how many times I try to reload.

It seems that their API is not stable and if you are plagued by the “Cannot read property…” error there will be days when you can Log In normally and other days when it will be impossible to Log In. There is no known workaround at the moment of writing.

About Robert Nakagawa

Robert was born in Akihabara, Tokyo, which of course meant he can never escape his geekiness. He spends his time installing mods for Skyrim, getting zeroed on GoT: Conquest and running the Editorial staff at Gaming Guide. He loves RPGs and strategy games.

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  1. hi can you post what you did to resolve the issue. I am having the exact same problem for 2 days, tried every solution that was posted without luck. thanks

    • Hi boba, thank you for your comment.

      After working fine for a few hours today, I am again experiencing the “Cannot read property…” error. I have tried every possible solution given to me by support without success. Unfortunately, there is no known workaround at the moment of writing.

      The only thing you can do is try again tomorrow or in a few days. There will be days when you can log in normally and other days when it will be impossible to log in.