diff --git a/migration/autotests/CMakeLists.txt b/migration/autotests/CMakeLists.txt
index cab0949f1..3b758df56 100644
--- a/migration/autotests/CMakeLists.txt
+++ b/migration/autotests/CMakeLists.txt
@@ -8,7 +8,7 @@ include_directories(
 set( kmail_migratekmail4configtest_source kmmigratekmail4configtest.cpp ../kmmigratekmail4config.cpp ../migrateinfo.cpp)
 add_executable(migratekmail4configtest ${kmail_migratekmail4configtest_source})
 ecm_mark_as_test(kmail-migratekmail4configtest)
-target_link_libraries( migratekmail4configtest Qt5::Test KF5::CoreAddons)
+target_link_libraries( migratekmail4configtest Qt5::Test KF5::CoreAddons KF5::ConfigCore)
 
 
 
diff --git a/migration/autotests/kmmigratekmail4configtest.cpp b/migration/autotests/kmmigratekmail4configtest.cpp
index 81200bd15..6ff73c4f1 100644
--- a/migration/autotests/kmmigratekmail4configtest.cpp
+++ b/migration/autotests/kmmigratekmail4configtest.cpp
@@ -34,6 +34,14 @@ void KMMigrateKMail4ConfigTest::shouldHaveDefaultValue()
 {
     KMMigrateKMail4Config migrate;
     QVERIFY(!migrate.start());
+    QVERIFY(migrate.configFileName().isEmpty());
+}
+
+void KMMigrateKMail4ConfigTest::shouldVerifyIfCheckIsNecessary()
+{
+    KMMigrateKMail4Config migrate;
+    //Invalid before config file is not set.
+    QVERIFY(!migrate.checkIfNecessary());
 }
 
 QTEST_MAIN(KMMigrateKMail4ConfigTest)
diff --git a/migration/autotests/kmmigratekmail4configtest.h b/migration/autotests/kmmigratekmail4configtest.h
index eea8f086f..cae7bacd3 100644
--- a/migration/autotests/kmmigratekmail4configtest.h
+++ b/migration/autotests/kmmigratekmail4configtest.h
@@ -28,6 +28,7 @@ public:
     ~KMMigrateKMail4ConfigTest();
 private Q_SLOTS:
     void shouldHaveDefaultValue();
+    void shouldVerifyIfCheckIsNecessary();
 
 };
 
diff --git a/migration/kmmigratekmail4config.cpp b/migration/kmmigratekmail4config.cpp
index e3dea1616..bbb528f28 100644
--- a/migration/kmmigratekmail4config.cpp
+++ b/migration/kmmigratekmail4config.cpp
@@ -17,6 +17,9 @@
 
 #include "kmmigratekmail4config.h"
 #include <kdelibs4migration.h>
+#include <KSharedConfig>
+#include <KConfigGroup>
+#include <QDebug>
 
 KMMigrateKMail4Config::KMMigrateKMail4Config(QObject *parent)
     : QObject(parent),
@@ -36,6 +39,10 @@ bool KMMigrateKMail4Config::start()
         return false;
     }
 
+    if (mConfigFileName.isEmpty()) {
+        qDebug() << " config file name not defined.";
+        return false;
+    }
     // Testing for kdehome
     Kdelibs4Migration migration;
     if (!migration.kdeHomeFound()) {
@@ -66,6 +73,14 @@ void KMMigrateKMail4Config::setConfigFileName(const QString &configFileName)
     mConfigFileName = configFileName;
 }
 
+void KMMigrateKMail4Config::writeConfig()
+{
+    KSharedConfig::Ptr config = KSharedConfig::openConfig(mConfigFileName, KConfig::SimpleConfig);
+    KConfigGroup grp = config->group(QStringLiteral("Migrate"));
+    grp.writeEntry(QStringLiteral("Version"), mVersion);
+    grp.sync();
+}
+
 void KMMigrateKMail4Config::migrateFolder(const MigrateInfo &info)
 {
     //TODO
@@ -88,7 +103,20 @@ void KMMigrateKMail4Config::setVersion(int version)
 
 bool KMMigrateKMail4Config::checkIfNecessary()
 {
-    //TODO compare mVersion with current version saved in config file.
+    if (mConfigFileName.isEmpty()) {
+        qDebug() << " config file name not defined.";
+        return false;
+    }
+    KSharedConfig::Ptr config = KSharedConfig::openConfig(mConfigFileName, KConfig::SimpleConfig);
+    if (config->hasGroup(QStringLiteral("Migrate"))) {
+        KConfigGroup grp = config->group(QStringLiteral("Migrate"));
+        const int lastVersion = grp.readEntry(QStringLiteral("Version"), 0);
+        if (lastVersion < mVersion) {
+            return true;
+        } else {
+            return false;
+        }
+    }
     return true;
 }
 
diff --git a/migration/kmmigratekmail4config.h b/migration/kmmigratekmail4config.h
index 37812efee..cf484f999 100644
--- a/migration/kmmigratekmail4config.h
+++ b/migration/kmmigratekmail4config.h
@@ -43,6 +43,7 @@ Q_SIGNALS:
     void migrateDone();
 
 private:
+    void writeConfig();
     void migrateFolder(const MigrateInfo &info);
     void migrateFile(const MigrateInfo &info);
     bool migrateConfig();