# Error when trying to create an event

**URL:** https://meta.discourse.org/t/error-when-trying-to-create-an-event/405428
**Category:** Bug
**Tags:** events, fixed
**Created:** [June 16, 2026, 6:08pm UTC](https://meta.discourse.org/t/error-when-trying-to-create-an-event/405428 "2026-06-16T18:08:30Z")
**Posts on this page:** 1
**Showing post:** 4

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### Author: ![awesomerobot](https://sea3.discourse-cdn.com/meta/user_avatar/meta.discourse.org/awesomerobot/32/142900_2.png) [@awesomerobot](https://meta.discourse.org/u/awesomerobot)
#### Post date: [June 19, 2026, 12:04pm UTC](https://meta.discourse.org/t/error-when-trying-to-create-an-event/405428/4 "2026-06-19T12:04:44Z")

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> [@newbit1337](#):
>
> I do have a user called “trust\_level\_0” for testing purposes and this might be an issue.

hah yes, I think this is certainly the issue… thanks for mentioning that

it’s an edge case, but we can guard against it, I’ve just merged an update that will avoid the error in the future

> <https://github.com/discourse/discourse/pull/41039>
>
> Reported here: https://meta.discourse.org/t/error-when-trying-to-create-an-event…/405428
> 
> Creating a public event could fail with "Validation failed: An event accepts only group names" on sites that happen to have a user whose username exactly matches an automatic group name (e.g. \`trust\_level\_0\`)
> 
> This change excludes valid group names before checking for username collisions.

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