diff --git a/src/cpp/HTTPInterface/LoginPage.cpp b/src/cpp/HTTPInterface/LoginPage.cpp
index 881dbe05a..e2e5fe1b3 100644
--- a/src/cpp/HTTPInterface/LoginPage.cpp
+++ b/src/cpp/HTTPInterface/LoginPage.cpp
@@ -38,6 +38,16 @@ void LoginPage::handleRequest(Poco::Net::HTTPServerRequest& request, Poco::Net::
 	auto langCatalog = lm->getFreeCatalog(lang);
 	
 	if(!form.empty()) {
+		auto langBtn = form.get("lang", "");
+		bool langUpdated = false;
+		if(langBtn != "") {
+			auto updatedLang = chooseLanguage(request, langBtn);
+			if(updatedLang != lang) {
+				lang = updatedLang;
+				langCatalog = lm->getFreeCatalog(lang);
+				langUpdated = true;
+			}
+		} 
 		auto email = form.get("login-email", "");
 		auto password = form.get("login-password", "");
 		
@@ -81,7 +91,7 @@ void LoginPage::handleRequest(Poco::Net::HTTPServerRequest& request, Poco::Net::
 				return;
 			}
 			
-		} else {
+		} else if(!langUpdated) {
 			addError(new Error(langCatalog->gettext("Login"), langCatalog->gettext("Username and password are needed!")));
 		}
 		
@@ -134,7 +144,7 @@ void LoginPage::handleRequest(Poco::Net::HTTPServerRequest& request, Poco::Net::
 	responseStream << "        <div class=\"col-12 logo-section\">\n";
 	responseStream << "          <a href=\"../../index.html\" class=\"logo\">\n";
 	responseStream << "            <img src=\"";
-#line 83 "F:\\Gradido\\gradido_login_server\\src\\cpsp\\login.cpsp"
+#line 93 "F:\\Gradido\\gradido_login_server\\src\\cpsp\\login.cpsp"
 	responseStream << ( ServerConfig::g_php_serverPath );
 	responseStream << "img/logo_schrift.webp\" alt=\"logo\" />\n";
 	responseStream << "          </a>\n";
@@ -144,22 +154,43 @@ void LoginPage::handleRequest(Poco::Net::HTTPServerRequest& request, Poco::Net::
 	responseStream << "        <div class=\"col-lg-5 col-md-7 col-sm-9 col-11 mx-auto\">\n";
 	responseStream << "          <div class=\"grid\">\n";
 	responseStream << "\t\t    ";
-#line 90 "F:\\Gradido\\gradido_login_server\\src\\cpsp\\login.cpsp"
+#line 100 "F:\\Gradido\\gradido_login_server\\src\\cpsp\\login.cpsp"
 	responseStream << ( getErrorsHtml() );
 	responseStream << "\n";
 	responseStream << "            <div class=\"grid-body\">\n";
-	responseStream << "              <form action=\"\" method=\"POST\">\n";
+	responseStream << "              <form action=\"";
+#line 102 "F:\\Gradido\\gradido_login_server\\src\\cpsp\\login.cpsp"
+	responseStream << ( ServerConfig::g_serverPath );
+	responseStream << "/\" method=\"POST\">\n";
+	responseStream << "\t\t\t  <input type=\"hidden\" name=\"lang\" value=\"";
+#line 103 "F:\\Gradido\\gradido_login_server\\src\\cpsp\\login.cpsp"
+	responseStream << ( LanguageManager::keyForLanguage(lang) );
+	responseStream << "\">\n";
 	responseStream << "                <div class=\"row pull-right-row\">\n";
 	responseStream << "                  <div class=\"equel-grid pull-right\">\n";
 	responseStream << "                    <div class=\"grid-body-small text-center\">\n";
-	responseStream << "                        <button id=\"flag-england\" name=\"lang\" value=\"en\" title=\"English\" type=\"submit\" class=\"btn btn-outline-secondary flag-btn\">\n";
+	responseStream << "                        <button id=\"flag-england\" name=\"lang\" value=\"en\" title=\"English\" type=\"submit\" ";
+#line 107 "F:\\Gradido\\gradido_login_server\\src\\cpsp\\login.cpsp"
+ if(lang != LANG_EN) { 	responseStream << "class=\"btn btn-outline-secondary flag-btn\"";
+#line 107 "F:\\Gradido\\gradido_login_server\\src\\cpsp\\login.cpsp"
+ } 
+						else { 	responseStream << "class=\"btn btn-secondary disabled flag-btn\" disabled";
+#line 108 "F:\\Gradido\\gradido_login_server\\src\\cpsp\\login.cpsp"
+ } 	responseStream << ">\n";
 	responseStream << "                          <span class=\"flag-england\"></span>\n";
 	responseStream << "                        </button>\n";
 	responseStream << "                    </div>\n";
 	responseStream << "                  </div>\n";
 	responseStream << "                  <div class=\"equel-grid pull-right\">\n";
 	responseStream << "                    <div class=\"grid-body-small text-center\">\n";
-	responseStream << "                        <button id=\"flag-germany\" name=\"lang\" value=\"de\" title=\"Deutsch\" type=\"submit\" class=\"btn btn-secondary disabled flag-btn\" disabled>\n";
+	responseStream << "                        <button id=\"flag-germany\" name=\"lang\" value=\"de\" title=\"Deutsch\" type=\"submit\" ";
+#line 115 "F:\\Gradido\\gradido_login_server\\src\\cpsp\\login.cpsp"
+ if(lang != LANG_DE) { 	responseStream << "class=\"btn btn-outline-secondary flag-btn\"";
+#line 115 "F:\\Gradido\\gradido_login_server\\src\\cpsp\\login.cpsp"
+ } 
+						else { 	responseStream << "class=\"btn btn-secondary disabled flag-btn\" disabled";
+#line 116 "F:\\Gradido\\gradido_login_server\\src\\cpsp\\login.cpsp"
+ } 	responseStream << ">\n";
 	responseStream << "                          <span class=\"flag-germany\"></span>\n";
 	responseStream << "                        </button>\n";
 	responseStream << "                    </div>\n";
@@ -169,27 +200,27 @@ void LoginPage::handleRequest(Poco::Net::HTTPServerRequest& request, Poco::Net::
 	responseStream << "                  <div class=\"col-lg-7 col-md-8 col-sm-9 col-12 mx-auto form-wrapper\">\n";
 	responseStream << "                    <div class=\"form-group input-rounded\">\n";
 	responseStream << "                      <input type=\"text\" class=\"form-control\" name=\"login-email\" placeholder=\"";
-#line 112 "F:\\Gradido\\gradido_login_server\\src\\cpsp\\login.cpsp"
+#line 125 "F:\\Gradido\\gradido_login_server\\src\\cpsp\\login.cpsp"
 	responseStream << ( langCatalog->gettext("E-Mail") );
 	responseStream << "\" />\n";
 	responseStream << "                    </div>\n";
 	responseStream << "                    <div class=\"form-group input-rounded\">\n";
 	responseStream << "                      <input type=\"password\" class=\"form-control\" name=\"login-password\" placeholder=\"";
-#line 115 "F:\\Gradido\\gradido_login_server\\src\\cpsp\\login.cpsp"
+#line 128 "F:\\Gradido\\gradido_login_server\\src\\cpsp\\login.cpsp"
 	responseStream << ( langCatalog->gettext("Password") );
 	responseStream << "\" />\n";
 	responseStream << "                    </div>\n";
 	responseStream << "                    <button type=\"submit\" name=\"submit\" class=\"btn btn-primary btn-block\">";
-#line 117 "F:\\Gradido\\gradido_login_server\\src\\cpsp\\login.cpsp"
+#line 130 "F:\\Gradido\\gradido_login_server\\src\\cpsp\\login.cpsp"
 	responseStream << ( langCatalog->gettext(" Login ") );
 	responseStream << "</button>\n";
 	responseStream << "                    <div class=\"signup-link\">\n";
 	responseStream << "                      <p>";
-#line 119 "F:\\Gradido\\gradido_login_server\\src\\cpsp\\login.cpsp"
+#line 132 "F:\\Gradido\\gradido_login_server\\src\\cpsp\\login.cpsp"
 	responseStream << ( langCatalog->gettext("You haven't any account yet? Please follow the link to create one.") );
 	responseStream << "</p>\n";
 	responseStream << "                      <a href=\"https://gradido.com\">";
-#line 120 "F:\\Gradido\\gradido_login_server\\src\\cpsp\\login.cpsp"
+#line 133 "F:\\Gradido\\gradido_login_server\\src\\cpsp\\login.cpsp"
 	responseStream << ( langCatalog->gettext("Create New Account") );
 	responseStream << "</a>\n";
 	responseStream << "                    </div>\n";
diff --git a/src/cpp/HTTPInterface/PageRequestMessagedHandler.cpp b/src/cpp/HTTPInterface/PageRequestMessagedHandler.cpp
index bf6899205..cf99db028 100644
--- a/src/cpp/HTTPInterface/PageRequestMessagedHandler.cpp
+++ b/src/cpp/HTTPInterface/PageRequestMessagedHandler.cpp
@@ -2,7 +2,9 @@
 
 #include "Poco/Net/HTTPServerRequest.h"
 
-const Poco::RegularExpression PageRequestMessagedHandler::mDetectLanguageGET("^/(?:[a-zA-Z0-9_-]*)/(en|de)");
+#include "../ServerConfig.h"
+
+const Poco::RegularExpression PageRequestMessagedHandler::mDetectLanguageGET("^(?:/[a-zA-Z0-9_-]*)?/(en|de)");
 
 Languages PageRequestMessagedHandler::chooseLanguage(Poco::Net::HTTPServerRequest& request, std::string post_lang /* =  std::string("") */)
 {
@@ -12,10 +14,11 @@ Languages PageRequestMessagedHandler::chooseLanguage(Poco::Net::HTTPServerReques
 	if (lang == LANG_NULL) {
 		// from URL
 		std::string uri = request.getURI();
-		std::string lang_str;
-		mDetectLanguageGET.extract(uri, lang_str);
-		if (lang_str.size() > 0) {
-			lang = LanguageManager::languageFromString(lang_str);
+		std::vector<std::string> matches;
+		//std::string lang_str;
+		mDetectLanguageGET.split(uri, matches);
+		if (matches.size() > 0) {
+			lang = LanguageManager::languageFromString(matches[matches.size()-1]);
 		}
 		else {
 			// from Header
@@ -29,5 +32,9 @@ Languages PageRequestMessagedHandler::chooseLanguage(Poco::Net::HTTPServerReques
 		}
 	}
 
+	if (lang == LANG_NULL) {
+		//lang = ServerConfig::g_default_locale;
+	}
+
 	return lang;
 }
\ No newline at end of file
diff --git a/src/cpp/ServerConfig.cpp b/src/cpp/ServerConfig.cpp
index e8264ab61..26f150d07 100644
--- a/src/cpp/ServerConfig.cpp
+++ b/src/cpp/ServerConfig.cpp
@@ -38,6 +38,7 @@ namespace ServerConfig {
 	EmailAccount g_EmailAccount;
 	int g_SessionTimeout = SESSION_TIMEOUT_DEFAULT;
 	std::string g_serverPath;
+	Languages g_default_locale;
 	std::string g_php_serverPath;
 	std::string g_php_serverHost;
 	Poco::Mutex g_TimeMutex;
@@ -95,6 +96,7 @@ namespace ServerConfig {
 		DISASM_FALSERET;
 		g_SessionTimeout = cfg.getInt("session.timeout", SESSION_TIMEOUT_DEFAULT);
 		g_serverPath = cfg.getString("loginServer.path", "");
+		g_default_locale = LanguageManager::languageFromString(cfg.getString("loginServer.default_locale"));
 		g_php_serverPath = cfg.getString("phpServer.url", "");
 		g_php_serverHost = cfg.getString("phpServer.host", "");
 		return true;
diff --git a/src/cpp/ServerConfig.h b/src/cpp/ServerConfig.h
index 611af97ed..ad19858af 100644
--- a/src/cpp/ServerConfig.h
+++ b/src/cpp/ServerConfig.h
@@ -9,6 +9,8 @@
 
 #include "tasks/CPUSheduler.h"
 
+#include "SingletonManager/LanguageManager.h"
+
 namespace ServerConfig {
 
 	enum Mnemonic_Types {
@@ -37,6 +39,7 @@ namespace ServerConfig {
 	extern EmailAccount g_EmailAccount;
 	extern int g_SessionTimeout;
 	extern std::string g_serverPath;
+	extern Languages g_default_locale;
 	extern std::string g_php_serverPath;
 	extern std::string g_php_serverHost;
 	extern Poco::Mutex g_TimeMutex;
diff --git a/src/cpp/SingletonManager/LanguageManager.cpp b/src/cpp/SingletonManager/LanguageManager.cpp
index 7d2bcb4ce..7d818f153 100644
--- a/src/cpp/SingletonManager/LanguageManager.cpp
+++ b/src/cpp/SingletonManager/LanguageManager.cpp
@@ -3,17 +3,23 @@
 #include "Poco/Path.h"
 #include "Poco/File.h"
 
+#include "../ServerConfig.h"
+
 #include <fstream>
 
 LanguageCatalog::LanguageCatalog(Languages lang) 
 	: mReferenceCount(1), mCatalog(nullptr), mThisLanguage(lang) 
 {
 	// TODO: Catalog init code
-	std::string path = Poco::Path::config() + "grd_login/LOCALE/" + LanguageManager::filenameForLanguage(lang) + ".po";
+	std::string path = Poco::Path::config() + "grd_login/LOCALE/";
+#if defined(_WIN32) || defined(_WIN64)
+	path = "./LOCALE/";
+#endif
+	path += LanguageManager::filenameForLanguage(lang) + ".po";
 	auto file = Poco::File(path);
 	if (file.exists()) {
 
-		std::ifstream ifs(path + LanguageManager::filenameForLanguage(lang) + ".po");
+		std::ifstream ifs(path);
 		std::string po_file{ std::istreambuf_iterator<char>{ifs}, std::istreambuf_iterator<char>() };
 
 		mCatalog = new spirit_po::default_catalog(spirit_po::default_catalog::from_range(po_file));
@@ -105,15 +111,24 @@ Languages LanguageManager::languageFromString(const std::string& language_key)
 	}
 	return LANG_NULL;
 }
+ std::string LanguageManager::keyForLanguage(Languages lang)
+{
+	 switch(lang) {
+	 case LANG_DE: return "de";
+	 case LANG_EN: return "en";
+	 }
+	 return "";
+}
+
 
 Poco::AutoPtr<LanguageCatalog> LanguageManager::getFreeCatalog(Languages lang)
 {
 	
 	if (lang >= LANG_COUNT) {
 		//printf("[LanguageManager::getFreeCatalog] invalid language: %d\n", lang);
-		mLogging.information("[LanguageManager::getFreeCatalog] invalid language: %d, set to default (en_GB)", (int)lang);
+		mLogging.information("[LanguageManager::getFreeCatalog] invalid language: %d, set to default (%s)", (int)lang, filenameForLanguage(ServerConfig::g_default_locale));
 		//return nullptr;
-		lang = LANG_EN;
+		lang = ServerConfig::g_default_locale;
 	}
 	lock();
 	if (mFreeCatalogs[lang].size() > 0) {
@@ -123,6 +138,7 @@ Poco::AutoPtr<LanguageCatalog> LanguageManager::getFreeCatalog(Languages lang)
 		unlock();
 		return result;
 	}
+	unlock();
 	Poco::AutoPtr<LanguageCatalog> result = new LanguageCatalog(lang);
 	return result;
 }
\ No newline at end of file
diff --git a/src/cpp/SingletonManager/LanguageManager.h b/src/cpp/SingletonManager/LanguageManager.h
index a40667edd..a24f5a807 100644
--- a/src/cpp/SingletonManager/LanguageManager.h
+++ b/src/cpp/SingletonManager/LanguageManager.h
@@ -79,6 +79,8 @@ public:
 	Poco::AutoPtr<LanguageCatalog> getFreeCatalog(Languages lang);
 	
 	static std::string filenameForLanguage(Languages lang);
+	// return empty for null
+	static std::string keyForLanguage(Languages lang);
 	static Languages languageFromString(const std::string& language_key);
 
 protected:
diff --git a/src/cpsp/login.cpsp b/src/cpsp/login.cpsp
index 326b529f7..730335b58 100644
--- a/src/cpsp/login.cpsp
+++ b/src/cpsp/login.cpsp
@@ -22,6 +22,16 @@
 	auto langCatalog = lm->getFreeCatalog(lang);
 	
 	if(!form.empty()) {
+		auto langBtn = form.get("lang", "");
+		bool langUpdated = false;
+		if(langBtn != "") {
+			auto updatedLang = chooseLanguage(request, langBtn);
+			if(updatedLang != lang) {
+				lang = updatedLang;
+				langCatalog = lm->getFreeCatalog(lang);
+				langUpdated = true;
+			}
+		} 
 		auto email = form.get("login-email", "");
 		auto password = form.get("login-password", "");
 		
@@ -65,7 +75,7 @@
 				return;
 			}
 			
-		} else {
+		} else if(!langUpdated) {
 			addError(new Error(langCatalog->gettext("Login"), langCatalog->gettext("Username and password are needed!")));
 		}
 		
@@ -89,18 +99,21 @@
           <div class="grid">
 		    <%= getErrorsHtml() %>
             <div class="grid-body">
-              <form action="" method="POST">
+              <form action="<%= ServerConfig::g_serverPath %>/" method="POST">
+			  <input type="hidden" name="lang" value="<%= LanguageManager::keyForLanguage(lang) %>">
                 <div class="row pull-right-row">
                   <div class="equel-grid pull-right">
                     <div class="grid-body-small text-center">
-                        <button id="flag-england" name="lang" value="en" title="English" type="submit" class="btn btn-outline-secondary flag-btn">
+                        <button id="flag-england" name="lang" value="en" title="English" type="submit" <% if(lang != LANG_EN) { %>class="btn btn-outline-secondary flag-btn"<% } 
+						else { %>class="btn btn-secondary disabled flag-btn" disabled<% } %>>
                           <span class="flag-england"></span>
                         </button>
                     </div>
                   </div>
                   <div class="equel-grid pull-right">
                     <div class="grid-body-small text-center">
-                        <button id="flag-germany" name="lang" value="de" title="Deutsch" type="submit" class="btn btn-secondary disabled flag-btn" disabled>
+                        <button id="flag-germany" name="lang" value="de" title="Deutsch" type="submit" <% if(lang != LANG_DE) { %>class="btn btn-outline-secondary flag-btn"<% } 
+						else { %>class="btn btn-secondary disabled flag-btn" disabled<% } %>>
                           <span class="flag-germany"></span>
                         </button>
                     </div>