diff --git a/src/mail.js b/src/mail.js
index 2f664420c..eaeb2c215 100644
--- a/src/mail.js
+++ b/src/mail.js
@@ -909,7 +909,7 @@ function addDomain(domain, callback) {
     assert.strictEqual(typeof domain, 'string');
     assert.strictEqual(typeof callback, 'function');
 
-    const dkimSelector = domain === config.adminDomain() ? 'cloudron' : (config.adminDomain().replace(/\./g, '') + '-cloudron');
+    const dkimSelector = domain === config.adminDomain() ? 'cloudron' : ('cloudron-' + config.adminDomain().replace(/\./g, ''));
 
     maildb.add(domain, { dkimSelector }, function (error) {
         if (error && error.reason === DatabaseError.ALREADY_EXISTS) return callback(new MailError(MailError.ALREADY_EXISTS, 'Domain already exists'));
diff --git a/src/routes/test/mail-test.js b/src/routes/test/mail-test.js
index 958f4d01f..56196a6df 100644
--- a/src/routes/test/mail-test.js
+++ b/src/routes/test/mail-test.js
@@ -239,7 +239,7 @@ describe('Mail API', function () {
                 callback(null, dnsAnswerQueue[hostname][type]);
             };
 
-            dkimDomain = 'admincom-cloudron._domainkey.' + DOMAIN_0.domain;
+            dkimDomain = 'cloudron-admincom._domainkey.' + DOMAIN_0.domain;
             spfDomain = DOMAIN_0.domain;
             mxDomain = DOMAIN_0.domain;
             dmarcDomain = '_dmarc.' + DOMAIN_0.domain;