diff --git a/src/java/davmail/exchange/ExchangeSession.java b/src/java/davmail/exchange/ExchangeSession.java
index 13734c15..d58ae199 100644
--- a/src/java/davmail/exchange/ExchangeSession.java
+++ b/src/java/davmail/exchange/ExchangeSession.java
@@ -507,17 +507,19 @@ public class ExchangeSession {
         }
 
         // add bcc and other properties
-        patchMethod = new PropPatchMethod(messageUrl);
-        try {
-            // update message with blind carbon copy and other flags
-            addProperties(patchMethod, properties);
-            int statusCode = wdr.retrieveSessionInstance().executeMethod(patchMethod);
-            if (statusCode != HttpStatus.SC_MULTI_STATUS) {
-                throw new IOException("Unable to patch message " + messageUrl + ": " + statusCode + " " + patchMethod.getStatusLine());
-            }
+        if (properties.size() > 0) {
+            patchMethod = new PropPatchMethod(messageUrl);
+            try {
+                // update message with blind carbon copy and other flags
+                addProperties(patchMethod, properties);
+                int statusCode = wdr.retrieveSessionInstance().executeMethod(patchMethod);
+                if (statusCode != HttpStatus.SC_MULTI_STATUS) {
+                    throw new IOException("Unable to patch message " + messageUrl + ": " + statusCode + " " + patchMethod.getStatusLine());
+                }
 
-        } finally {
-            patchMethod.releaseConnection();
+            } finally {
+                patchMethod.releaseConnection();
+            }
         }
     }
 
diff --git a/src/java/davmail/imap/ImapConnection.java b/src/java/davmail/imap/ImapConnection.java
index 80455c60..5b7e6903 100644
--- a/src/java/davmail/imap/ImapConnection.java
+++ b/src/java/davmail/imap/ImapConnection.java
@@ -41,6 +41,7 @@ public class ImapConnection extends AbstractConnection {
         String commandId = null;
         StringTokenizer tokens;
         try {
+            ExchangeSessionFactory.checkConfig();
             sendClient("* OK [CAPABILITY IMAP4REV1 AUTH=LOGIN] IMAP4rev1 DavMail server ready");
             for (; ;) {
                 line = readClient();
@@ -368,6 +369,7 @@ public class ImapConnection extends AbstractConnection {
                                         }
                                     }
                                     // skip optional date
+                                    // TODO : replace datereceived
                                     String dateOrSize = tokens.nextToken();
                                     if (tokens.hasMoreTokens()) {
                                         dateOrSize = tokens.nextToken();
@@ -428,7 +430,7 @@ public class ImapConnection extends AbstractConnection {
                 if (commandId != null) {
                     sendClient(commandId + " BAD unable to handle request: " + e.getMessage());
                 } else {
-                    sendClient("* BAD unable to handle request: " + e.getMessage());
+                    sendClient("* BYE unable to handle request: " + e.getMessage());
                 }
             } catch (IOException e2) {
                 DavGatewayTray.warn("Exception sending error to client", e2);