diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1f2a833..4da984c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -134,7 +134,6 @@ IF (UNIX)
 ENDIF (UNIX)
 
 # check if Doxygen is installed
-
 if (BUILD_DOC)
     message(STATUS "config of DOxygen build")
     find_package(Doxygen)
@@ -157,4 +156,4 @@ if (BUILD_DOC)
         message(STATUS "Doxygen need to be installed to generate the doxygen documentation")
     endif (DOXYGEN_FOUND)
     message("")
-endif (BUILD_DOC)
+endif (BUILD_DOC)
\ No newline at end of file
diff --git a/src/IPRefresher.cpp b/src/IPRefresher.cpp
index 2e2b32b..6c22b99 100644
--- a/src/IPRefresher.cpp
+++ b/src/IPRefresher.cpp
@@ -23,7 +23,7 @@ void IPRefresher::checkIPAdress(bool force) {
     std::string ip = ipapi.getGlobalIp();
 
     if (ip.empty()) {
-        //no internet connection
+        //no internet connection (or other error)
         logger.logToLogfile("[WARNING] no internet connection");
         Logger::warning("no internet connection");
     } else {
@@ -37,7 +37,7 @@ void IPRefresher::checkIPAdress(bool force) {
             Logger::message("ip changed! -- from :" + oldip + "to: " + ip);
 
             DynuAPI dynu;
-            dynu.init(Credentials::dynuapikey,Credentials::domainid,Credentials::domainname);
+            dynu.init(Credentials::dynuapikey, Credentials::domainid, Credentials::domainname);
 
             if (dynu.refreshIp(ip)) {
                 TelegramAPI tele;
@@ -55,14 +55,18 @@ void IPRefresher::checkIPAdress(bool force) {
 }
 
 IPRefresher::IPRefresher() {
-
+    // default constructor
 }
 
 IPRefresher::IPRefresher(bool loop) {
-    Logger::message("startup of service");
-    while (loop) {
-        Logger::message("starting check");
-        checkIPAdress(false);
-        std::this_thread::sleep_for(std::chrono::milliseconds(300000));
+    if (Credentials::readCredentials()) {
+        Logger::message("startup of service");
+        while (loop) {
+            Logger::message("starting check");
+            checkIPAdress(false);
+            std::this_thread::sleep_for(std::chrono::milliseconds(300000));
+        }
+    } else {
+        std::cout << "incorrect credentials!" << std::endl;
     }
 }
diff --git a/src/main.cpp b/src/main.cpp
index 654bb47..9c238be 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -5,10 +5,6 @@
 #include <Credentials.h>
 
 int main(int argc, char *argv[]) {
-    if (!Credentials::readCredentials()) {
-        std::cout << "incorrect credentials!" << std::endl;
-        return -1;
-    }
     if (argc > 1) {
         std::string firstarg(argv[1]);
         if (firstarg == "-h" || firstarg == "--help") {
@@ -21,7 +17,12 @@ int main(int argc, char *argv[]) {
             std::cout << "Version " << Version::VERSION << std::endl;
         } else if (firstarg == "-f" || firstarg == "--force") {
             IPRefresher ipr;
-            ipr.checkIPAdress(true);
+            if (Credentials::readCredentials()) {
+                ipr.checkIPAdress(true);
+            } else {
+                std::cout << "incorrect credentials!" << std::endl;
+            }
+
         } else if (firstarg == "-l" || firstarg == "--loop") {
             IPRefresher(true);
         } else {
@@ -30,7 +31,12 @@ int main(int argc, char *argv[]) {
     } else {
         IPRefresher ipr;
         Logger::message("starting check");
-        ipr.checkIPAdress(false);
+        if (Credentials::readCredentials()) {
+            ipr.checkIPAdress(false);
+        } else {
+            std::cout << "incorrect credentials!" << std::endl;
+        }
+
     }
 
     return 0;