diff --git a/parameterManager.cpp b/parameterManager.cpp
index 99d5c8d..760ee6d 100644
--- a/parameterManager.cpp
+++ b/parameterManager.cpp
@@ -174,7 +174,7 @@ int loadDefaulOptions(Settings &settings)
 
         } else if (what == "default-CheckMaxDirs") {
             settings.default_maxDirs = atoi(data.c_str());
-            if(std::to_string(settings.default_maxDirs) != data ) {
+            if(!isNumber(data) ) {
                 std::cout << " => Error_Defaults: default-CheckMaxDirs: Ungültige Zahl: " << data << std::endl;
                 return 18;
             }
@@ -184,7 +184,7 @@ int loadDefaulOptions(Settings &settings)
 
         } else if (what == "default-maxThreads") {
             settings.maxThreads = static_cast<unsigned>(atoi(data.c_str()));
-            if(std::to_string(settings.maxThreads) != data ) {
+            if(isNumber(data) ) {
                 std::cout << " => Error_Defaults: Thread-Max Ungültige Zahl: " << data << std::endl;
                 return 18;
             } else if (settings.maxThreads > 10) {
@@ -322,7 +322,7 @@ int unterOption_default(Settings *settings, int argc, char ** argv)
                 if(!optarg)
                     break;
                 settings->startEpisode = atoi(optarg);
-                if (std::to_string(settings->startEpisode) != optarg) {
+                if (!isNumber(optarg)) {
                     std::cout << " => Error: -e [Folge]: '" << optarg << "' ist keine Zahl." << std::endl;
                     return 11;
                 } else if (settings->startEpisode <= 0) {
@@ -336,7 +336,7 @@ int unterOption_default(Settings *settings, int argc, char ** argv)
                 if(!optarg)
                     break;
                 settings->stopEpisode = atoi(optarg);
-                if (std::to_string(settings->stopEpisode) != optarg) {
+                if (!isNumber(optarg)) {
                     std::cout << " => Error: -E [Folge]: '" << optarg << "' ist keine Zahl." << std::endl;
                     return 14;
                 } else if (settings->debugMode)
@@ -346,7 +346,7 @@ int unterOption_default(Settings *settings, int argc, char ** argv)
                 if(!optarg)
                     break;
                 settings->startSeason = atoi(optarg);
-                if (std::to_string(settings->startSeason) != optarg) {
+                if (!isNumber(optarg)) {
                     std::cout << " => Error: -s [Staffel]: '" << optarg << "' ist keine Zahl." << std::endl;
                     return 15;
                 } else if (settings->startSeason < 0) {
@@ -359,7 +359,7 @@ int unterOption_default(Settings *settings, int argc, char ** argv)
                 if(!optarg)
                     break;
                 settings->stopSeason = atoi(optarg);
-                if (std::to_string(settings->stopSeason) != optarg) {
+                if (!isNumber(optarg)) {
                     std::cout << " => Error: -S [Staffel]: '" << optarg << "' ist keine Zahl." << std::endl;
                     return 18;
                 } else if(settings->debugMode)
@@ -375,8 +375,8 @@ int unterOption_default(Settings *settings, int argc, char ** argv)
                 if(!optarg)
                     break;
                 settings->default_maxDirs = atoi(optarg);
-                if(std::to_string(settings->default_maxDirs) != std::string(optarg) ) {
-                    std::cout << " => Error: [-D]: Invalid Count: " << optarg << std::endl;
+                if(!isNumber(optarg)) {
+                    std::cout << " => Error: [-D]: Ungültige Zahl: " << optarg << std::endl;
                     return 18;
                 }
                 if(settings->debugMode)
@@ -387,7 +387,7 @@ int unterOption_default(Settings *settings, int argc, char ** argv)
                 if(!optarg)
                     break;
                 settings->maxThreads = static_cast<unsigned>(atoi(optarg));
-                if(std::to_string(settings->maxThreads) != std::string(optarg) ) {
+                if(!isNumber(optarg)) {
                     std::cout << " => Error: [-t]: Thread-Max: Ungültige Zahl: " << optarg << std::endl;
                     return 18;
                 } else if (settings->maxThreads > 10 && !settings->debugMode) {