New launcher giving 'failed to create child event loop' error

I'm having an ERROR similar to yours
 

this has to do with java services being messed up atm

Possible relation to MCL-19984

Seems like the launcher has 0 permissions to overwrite/read/load files

Unable to create a firewall.

This launcher was 100% rushed to Xbox and not fully tested. A single test would already solve these issues but clearly not.

same problem

Relation to MC-34749

same problem here

I'm having this problem when I try to open a world. Minecraft itself will launch, but when I try to open a world the game will crash and give me the same error message. I've tried turning off AntiVirus, but nothing seems to do the trick. 

Jacob Deneke
I'm having this problem when I try to open a world. Minecraft itself will launch, but when I try to open a world the game will crash and give me the same error message. I've tried turning off AntiVirus, but nothing seems to do the trick.

Your best bet since the new Xbox Minecraft Launcher I mean (NEW Windows App) has ZERO permissions to read/write to the disk which is the CAUSE ROOT of all these issues. Use the Old Launcher instead despite the "Go to new launcher button" since you can't do of the following:

• Can't create/load worlds (Read and Write Perm Issue)

• Update Minecraft Dungeons (Write Perm Issue)

• Create New Profiles (Write Perm Issue)

• Set Firewall Correctly For Multiplayer (Read/Write Perm Issue)

• Unable connect to any Minecraft server (Result of Firewall Issue due to Read/Write Perm Issue)

• Unable to save profiles (Write Perm Issue)

• Unable to load old profiles (Read Perm Issue)

• Unable to save login details (Read/Write Perm Issue)

• Unable to save skins (Write Perm Issue)

• Unable to see old skins (Read Perm Issue)

Issue Resolved. The new update from the Microsoft Store fixed this particular issue and probably the read/write perm issue.