diff --git a/lib/Service/FederatedUserService.php b/lib/Service/FederatedUserService.php
index 2f9aebbad..a77864a8f 100644
--- a/lib/Service/FederatedUserService.php
+++ b/lib/Service/FederatedUserService.php
@@ -689,6 +689,10 @@ public function getFederatedUser(string $federatedId, int $type = Member::TYPE_S
 	 * @return FederatedUser
 	 */
 	public function generateFederatedUser(string $federatedId, int $type = 0): FederatedUser {
+		if ($type === Member::TYPE_MAIL) {
+			$federatedId = strtolower($federatedId);
+		}
+
 		try {
 			return $this->getFederatedUser($federatedId, $type);
 		} catch (Exception $e) {