diff --git a/crypto/src/openpgp/PgpPublicKey.cs b/crypto/src/openpgp/PgpPublicKey.cs
index 672ce9548..ed8a1c25c 100644
--- a/crypto/src/openpgp/PgpPublicKey.cs
+++ b/crypto/src/openpgp/PgpPublicKey.cs
@@ -1100,7 +1100,7 @@ private static PgpPublicKey RemoveCert(PgpPublicKey	key, IUserDataPacket id, Pgp
             PgpPublicKey returnKey = new PgpPublicKey(key);
             bool found = false;
 
-            for (int i = 0; i < returnKey.ids.Count; i++)
+            for (int i = returnKey.ids.Count-1; i >= 0 ; i--)
             {
                 if (id.Equals(returnKey.ids[i]))
                 {