Index: program/include/rcube_imap.php
===================================================================
--- program/include/rcube_imap.php	(revision 2871)
+++ program/include/rcube_imap.php	(working copy)
@@ -1609,7 +1609,10 @@
       // increase messagecount of the target mailbox
       $this->_set_messagecount($mailbox, 'ALL', 1);
       }
-          
+
+    raise_error(array('code' => 403, 'type' => 'imap', 'file' => __FILE__,
+                      'message' => $this->conn->error), TRUE, FALSE);
+
     return $saved;
     }
 
Index: program/lib/imap.inc
===================================================================
--- program/lib/imap.inc	(revision 2871)
+++ program/lib/imap.inc	(working copy)
@@ -2386,7 +2386,12 @@
 	$request = 'a APPEND "' . iil_Escape($folder) .'" (\\Seen) {' . $len . '}';
     
 	if (iil_PutLine($fp, $request)) {
-		$line = iil_ReadLine($fp, 100);		
+		$line = iil_ReadLine($fp, 100);
+		$result = (iil_ParseResult($line) == 0);
+		if (!$result) {
+			$conn->error .= "Cannot write to folder: ".$line."\n";
+			return false;
+		}
 		$sent = iil_PutLine($fp, $message);
 		do {
 			$line=iil_ReadLine($fp);
@@ -2429,6 +2434,11 @@
 	$bytes_sent = 0;
 	if (iil_PutLine($fp, $request)) {
 		$line = iil_ReadLine($fp, 100);
+
+		if (!$result) {
+			$conn->error .= "Cannot write to folder: ".$line."\n";
+			return false;
+		}
 				
 		//send file
 		while (!feof($in_fp)) {