RocketChat/Rocket.Chat · error · Meteor.Error

Custom_Emoji_Error_Name_Or_Alias_Already_In_Use

Custom_Emoji_Error_Name_Or_Alias_Already_In_Use

Error message

The custom emoji or one of its aliases is already in use

What it means

Error "The custom emoji or one of its aliases is already in use" thrown in RocketChat/Rocket.Chat.

Source

Thrown at apps/meteor/server/lib/media/emoji-custom/lib/insertOrUpdateEmoji.ts:76

				input: emojiData.aliases,
				field: 'Alias_Set',
			});
		}
		aliases = emojiData.aliases
			.split(/\s*,\s*/)
			.filter(Boolean)
			.map((alias) => limax(alias, { replacement: '_' }))
			.filter((alias) => alias !== emojiData.name);
	}

	emojiData.extension = emojiData.extension === 'svg+xml' ? 'png' : emojiData.extension;

	const conflictingEmoji = await EmojiCustom.findOneByNamesOrAliases([emojiData.name, ...aliases], emojiData._id, {
		projection: { _id: 1 },
	});

	if (conflictingEmoji) {
		throw new Meteor.Error('Custom_Emoji_Error_Name_Or_Alias_Already_In_Use', 'The custom emoji or one of its aliases is already in use', {
			method: 'insertOrUpdateEmoji',
		});
	}

	if (typeof emojiData.extension === 'undefined') {
		throw new Meteor.Error('error-the-field-is-required', 'The custom emoji file is required', {
			method: 'insertOrUpdateEmoji',
		});
	}

	if (!emojiData._id) {
		// insert emoji
		const createEmoji = {
			name: emojiData.name,
			aliases,
			extension: emojiData.extension,
		};

View on GitHub (pinned to b2c16d5842)

Solutions

1. Choose a different emoji name or aliases; an existing custom emoji already uses that name or one of the aliases.
2. Remove the conflicting alias or rename the existing custom emoji first.

When it happens

Trigger: Thrown at apps/meteor/server/lib/media/emoji-custom/lib/insertOrUpdateEmoji.ts:76 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of RocketChat/Rocket.Chat@b2c16d5842 (2026-08-18). Data as JSON: /api/errors/fe7ea9a7ad57c4cd. Report an issue: GitHub.