diff --git a/core/account.cpp b/core/account.cpp
index 9ef85ee..90c5b42 100644
--- a/core/account.cpp
+++ b/core/account.cpp
@@ -219,6 +219,8 @@ void Core::Account::onClientConnected()
 
 void Core::Account::onClientDisconnected()
 {
+    cancelHistoryRequests();
+    pendingVCardRequests.clear();
     clearConferences();
     if (state != Shared::ConnectionState::disconnected) {
         if (reconnectTimes > 0) {
@@ -854,18 +856,20 @@ void Core::Account::onMamMessageReceived(const QString& queryId, const QXmppMess
 {
     if (msg.id().size() > 0 && (msg.body().size() > 0 || msg.outOfBandUrl().size() > 0)) {
         std::map<QString, QString>::const_iterator itr = achiveQueries.find(queryId);
-        QString jid = itr->second;
-        RosterItem* item = getRosterItem(jid);
-        
-        Shared::Message sMsg(static_cast<Shared::Message::Type>(msg.type()));
-        initializeMessage(sMsg, msg, false, true, true);
-        sMsg.setState(Shared::Message::State::sent);
-        
-        QString oId = msg.replaceId();
-        if (oId.size() > 0) {
-            item->correctMessageInArchive(oId, sMsg);
-        } else {
-            item->addMessageToArchive(sMsg);
+        if (itr != achiveQueries.end()) {
+            QString jid = itr->second;
+            RosterItem* item = getRosterItem(jid);
+            
+            Shared::Message sMsg(static_cast<Shared::Message::Type>(msg.type()));
+            initializeMessage(sMsg, msg, false, true, true);
+            sMsg.setState(Shared::Message::State::sent);
+            
+            QString oId = msg.replaceId();
+            if (oId.size() > 0) {
+                item->correctMessageInArchive(oId, sMsg);
+            } else {
+                item->addMessageToArchive(sMsg);
+            }
         }
     } 
     
@@ -896,10 +900,15 @@ void Core::Account::requestArchive(const QString& jid, int count, const QString&
     
     if (contact == 0) {
         qDebug() << "An attempt to request archive for" << jid << "in account" << name << ", but the contact with such id wasn't found, skipping";
-        emit responseArchive(contact->jid, std::list<Shared::Message>());
+        emit responseArchive(jid, std::list<Shared::Message>());
         return;
     }
     
+    if (state != Shared::ConnectionState::connected) {
+        qDebug() << "An attempt to request archive for" << jid << "in account" << name << ", but the account is not online, skipping";
+        emit responseArchive(contact->jid, std::list<Shared::Message>());
+    }
+    
     if (contact->getArchiveState() == RosterItem::empty && before.size() == 0) {
         QXmppMessage msg(getFullJid(), jid, "", "");
         QString last = Shared::generateUUID();
@@ -952,14 +961,16 @@ void Core::Account::onContactNeedHistory(const QString& before, const QString& a
 void Core::Account::onMamResultsReceived(const QString& queryId, const QXmppResultSetReply& resultSetReply, bool complete)
 {
     std::map<QString, QString>::const_iterator itr = achiveQueries.find(queryId);
-    QString jid = itr->second;
-    achiveQueries.erase(itr);
-    
-    RosterItem* ri = getRosterItem(jid);
-    
-    if (ri != 0) {
-        qDebug() << "Flushing messages for" << jid;
-        ri->flushMessagesToArchive(complete, resultSetReply.first(), resultSetReply.last());
+    if (itr != achiveQueries.end()) {
+        QString jid = itr->second;
+        achiveQueries.erase(itr);
+        
+        RosterItem* ri = getRosterItem(jid);
+        
+        if (ri != 0) {
+            qDebug() << "Flushing messages for" << jid;
+            ri->flushMessagesToArchive(complete, resultSetReply.first(), resultSetReply.last());
+        }
     }
 }
 
@@ -1743,3 +1754,14 @@ void Core::Account::onReceiptReceived(const QString& jid, const QString& id)
     }
 }
 
+void Core::Account::cancelHistoryRequests()
+{
+    for (const std::pair<QString, Conference*>& pair : conferences) {
+        pair.second->clearArchiveRequests();
+    }
+    for (const std::pair<QString, Contact*>& pair : contacts) {
+        pair.second->clearArchiveRequests();
+    }
+    achiveQueries.clear();
+}
+
diff --git a/core/account.h b/core/account.h
index 386835c..b706916 100644
--- a/core/account.h
+++ b/core/account.h
@@ -236,6 +236,7 @@ private:
     void logMessage(const QXmppMessage& msg, const QString& reason = "Message wasn't handled: ");
     void storeConferences();
     void clearConferences();
+    void cancelHistoryRequests();
     void sendMessageWithLocalUploadedFile(Shared::Message msg, const QString& url);
     RosterItem* getRosterItem(const QString& jid);
 };
diff --git a/core/rosteritem.cpp b/core/rosteritem.cpp
index c25b339..8260eec 100644
--- a/core/rosteritem.cpp
+++ b/core/rosteritem.cpp
@@ -518,3 +518,13 @@ Shared::VCard Core::RosterItem::handleResponseVCard(const QXmppVCardIq& card, co
     return vCard;
 }
 
+void Core::RosterItem::clearArchiveRequests()
+{
+    syncronizing = false;
+    requestedCount = 0;
+    requestedBefore = "";
+    hisoryCache.clear();
+    responseCache.clear();
+    appendCache.clear();
+    requestCache.clear();
+}
diff --git a/core/rosteritem.h b/core/rosteritem.h
index 47470b1..cecd2e4 100644
--- a/core/rosteritem.h
+++ b/core/rosteritem.h
@@ -76,6 +76,7 @@ public:
     virtual void handlePresence(const QXmppPresence& pres) = 0;
     
     bool changeMessage(const QString& id, const QMap<QString, QVariant>& data);
+    void clearArchiveRequests();
     
 signals:
     void nameChanged(const QString& name);