diff --git a/backend/api/server.py b/backend/api/server.py
index 48b95ef..d83520b 100644
--- a/backend/api/server.py
+++ b/backend/api/server.py
@@ -4556,28 +4556,6 @@ def _safe_account_id(account_id: str | None) -> str:
     return normalized[:80] or 'default'
 
 
-_XIAOMI_EMAIL_RE = re.compile(r'^([\w.-]+)@xiaomi\.com$', re.IGNORECASE)
-_EMAIL_ACCOUNT_ID_RE = re.compile(r'^[a-z0-9._-]{2,40}$')
-
-
-def _account_id_from_email(email: str | None) -> str | None:
-    """Validate a Xiaomi email and return its prefix as account_id.
-
-    The prefix is lowercased and must satisfy the platform account_id rule:
-    only lowercase letters / digits / dot / underscore / dash, length 2-40.
-    Returns None if the email or prefix is invalid (caller must reject).
-    """
-    if not isinstance(email, str):
-        return None
-    match = _XIAOMI_EMAIL_RE.match(email.strip())
-    if not match:
-        return None
-    prefix = match.group(1).lower()
-    if not _EMAIL_ACCOUNT_ID_RE.match(prefix):
-        return None
-    return prefix
-
-
 def _linux_accounts_enabled() -> bool:
     return os.environ.get(LINUX_ACCOUNT_ENV, '').strip().lower() in {
         '1',
diff --git a/frontend/app/lib/claw-auth.ts b/frontend/app/lib/claw-auth.ts
index ee5c356..2ba811f 100644
--- a/frontend/app/lib/claw-auth.ts
+++ b/frontend/app/lib/claw-auth.ts
@@ -103,6 +103,7 @@ export async function registerByEmail(email: string, password: string) {
 		createdAt: new Date().toISOString(),
 	};
 	usersFile.users.push(account);
+	await ensureLinuxAccount(account.id, password);
 	await writeUsers(usersFile);
 	await createAccountDirectories(account.id);
 	return createSession(account);
@@ -121,6 +122,7 @@ export async function loginByEmail(email: string, password: string) {
 	if (!verifyPassword(password, account.passwordHash)) {
 		throw new Error("邮箱或密码错误");
 	}
+	await ensureLinuxAccount(account.id, password);
 	await createAccountDirectories(account.id);
 	return createSession(account);
 }