diff --git a/MailKit/Net/Imap/ImapFolder.cs b/MailKit/Net/Imap/ImapFolder.cs
index 4edb530c56..c9614dc6c9 100644
--- a/MailKit/Net/Imap/ImapFolder.cs
+++ b/MailKit/Net/Imap/ImapFolder.cs
@@ -907,7 +907,7 @@ async Task<IMailFolder> CreateAsync (ImapCommand ic, string encodedName, bool sp
 		/// <paramref name="name"/> is <c>null</c>.
 		/// </exception>
 		/// <exception cref="System.ArgumentException">
-		/// <paramref name="name"/> is empty.
+		/// <paramref name="name"/> is empty or invalid.
 		/// </exception>
 		/// <exception cref="System.ObjectDisposedException">
 		/// The <see cref="ImapClient"/> has been disposed.
@@ -954,7 +954,7 @@ public override IMailFolder Create (string name, bool isMessageFolder, Cancellat
 		/// <paramref name="name"/> is <c>null</c>.
 		/// </exception>
 		/// <exception cref="System.ArgumentException">
-		/// <paramref name="name"/> is empty.
+		/// <paramref name="name"/> is empty or invalid.
 		/// </exception>
 		/// <exception cref="System.ObjectDisposedException">
 		/// The <see cref="ImapClient"/> has been disposed.
@@ -1061,7 +1061,7 @@ ImapCommand QueueCreateCommand (string name, IEnumerable<SpecialFolder> specialU
 		/// <para><paramref name="specialUses"/> is <c>null</c>.</para>
 		/// </exception>
 		/// <exception cref="System.ArgumentException">
-		/// <paramref name="name"/> is empty.
+		/// <paramref name="name"/> is empty or invalid.
 		/// </exception>
 		/// <exception cref="System.ObjectDisposedException">
 		/// The <see cref="ImapClient"/> has been disposed.
@@ -1113,7 +1113,7 @@ public override IMailFolder Create (string name, IEnumerable<SpecialFolder> spec
 		/// <para><paramref name="specialUses"/> is <c>null</c>.</para>
 		/// </exception>
 		/// <exception cref="System.ArgumentException">
-		/// <paramref name="name"/> is empty.
+		/// <paramref name="name"/> is empty or invalid.
 		/// </exception>
 		/// <exception cref="System.ObjectDisposedException">
 		/// The <see cref="ImapClient"/> has been disposed.