diff --git a/app/src/main/java/eu/faircode/email/FragmentCompose.java b/app/src/main/java/eu/faircode/email/FragmentCompose.java
index 61945417b3..08f121c6d5 100644
--- a/app/src/main/java/eu/faircode/email/FragmentCompose.java
+++ b/app/src/main/java/eu/faircode/email/FragmentCompose.java
@@ -2640,7 +2640,7 @@ public class FragmentCompose extends FragmentBase {
                                     Intent intent = new Intent(OpenPgpApi.ACTION_GET_KEY);
                                     intent.putExtra(OpenPgpApi.EXTRA_KEY_ID, pgpSignKeyId);
                                     intent.putExtra(OpenPgpApi.EXTRA_MINIMIZE, true);
-                                    intent.putExtra(OpenPgpApi.EXTRA_MINIMIZE_USER_ID, identity.email);
+                                    intent.putExtra(OpenPgpApi.EXTRA_MINIMIZE_USER_ID, identity.email.toLowerCase());
                                     intent.putExtra(OpenPgpApi.EXTRA_REQUEST_ASCII_ARMOR, true);
                                     intent.putExtra(BuildConfig.APPLICATION_ID, largs);
                                     return intent;
@@ -2660,7 +2660,7 @@ public class FragmentCompose extends FragmentBase {
                                 Intent intent = new Intent(OpenPgpApi.ACTION_GET_KEY);
                                 intent.putExtra(OpenPgpApi.EXTRA_KEY_ID, pgpSignKeyId);
                                 intent.putExtra(OpenPgpApi.EXTRA_MINIMIZE, true);
-                                intent.putExtra(OpenPgpApi.EXTRA_MINIMIZE_USER_ID, identity.email);
+                                intent.putExtra(OpenPgpApi.EXTRA_MINIMIZE_USER_ID, identity.email.toLowerCase());
                                 intent.putExtra(OpenPgpApi.EXTRA_REQUEST_ASCII_ARMOR, true);
                                 intent.putExtra(BuildConfig.APPLICATION_ID, largs);
                                 return intent;