laurent22/joplin · error · ErrorUnprocessableEntity

there is already a user with this email

Error message

there is already a user with this email: ${user.email}

What it means

UserModel.validate throws ErrorUnprocessableEntity('there is already a user with this email') when the email being saved is already owned by a different user. validate loads the user by email and only accepts the match if it is the same record (existingUser.id === user.id), so updating your own email to itself is allowed.

Solutions

1. Choose a different email address for the account.
2. If the account exists, update/reuse the existing user record instead of creating a new one.
3. Check availability first via loadByEmail() before saving.

Example fix

// before
await models.user().save({ email: 'taken@example.com', password: 'x' }, { isNew: true });
// after
const existing = await models.user().loadByEmail('taken@example.com');
if (existing) throw new Error('Email already registered');
await models.user().save({ email: 'taken@example.com', password: 'x' }, { isNew: true });

const existing = await models.user().loadByEmail(email); if (existing && existing.id !== userId) throw new Error('Email already in use');

try { await models.user().save(user, opts); } catch (e) { if (/already a user with this email/.test(e.message)) /* show 'email taken' UI */; }

When it happens

Trigger: Creating a new user with an email that already exists, or updating a user's email to one already taken by another account.

Common situations: Signup with an email that was previously registered; admin editing a user's email to a colleague's address; re-running an import script that creates duplicates.

Related errors

• email must be set
• Full name must be at most 256 characters
• password must be set
• Should include @ in email address, email
• Ambiguous notebook " ". Please use notebook id instead -…

AI-assisted analysis of laurent22/joplin@981a03c5c9 (2026-09-17). Data as JSON: /api/errors/770fdcc281dff71f. Report an issue: GitHub.

Appendix: source

Thrown at packages/server/src/models/UserModel.ts:475

	protected async validate(object: User, options: ValidateOptions = {}): Promise<User> {
		const user: User = await super.validate(object, options);

		// Note that we don't validate the password here because it's already
		// been hashed by then.
		if (options.isNew) {
			if (!user.email) throw new ErrorUnprocessableEntity('email must be set');
			if ('email' in user && !user.email.includes('@')) throw new ErrorUnprocessableEntity(`Should include @ in email address, email: ${user.email}`);
			if (!user.password && !user.must_set_password) throw new ErrorUnprocessableEntity('password must be set');
		} else {
			if ('email' in user && !user.email) throw new ErrorUnprocessableEntity('email must be set');
			if (user.email && !user.email.includes('@')) throw new ErrorUnprocessableEntity(`Should include @ in email address, email: ${user.email}`);
			if ('password' in user && !user.password) throw new ErrorUnprocessableEntity('password must be set');
		}

		if (user.email) {
			const existingUser = await this.loadByEmail(user.email);
			if (existingUser && existingUser.id !== user.id) throw new ErrorUnprocessableEntity(`there is already a user with this email: ${user.email}`);
			// See https://www.rfc-editor.org/errata_search.php?rfc=3696&eid=1690 (found via https://stackoverflow.com/a/574698)
			if (user.email.length > 254) throw new ErrorUnprocessableEntity('Please enter an email address between 0 and 254 characters');
			validateEmail(user.email);
		}

		if (user.full_name && user.full_name.length > 256) throw new ErrorUnprocessableEntity('Full name must be at most 256 characters');

		return super.validate(user, options);
	}

	// public async delete(id: string): Promise<void> {
	// 	const shares = await this.models().share().sharesByUser(id);

	// 	await this.withTransaction(async () => {
	// 		await this.models().item().deleteExclusivelyOwnedItems(id);
	// 		await this.models().share().delete(shares.map(s => s.id));
	// 		await this.models().userItem().deleteByUserId(id);
	// 		await this.models().session().deleteByUserId(id);

View on GitHub (pinned to 981a03c5c9)