diff --git a/app/gui/oven_control/config.cpp b/app/gui/oven_control/config.cpp
index e6692f1..c1ce186 100644
--- a/app/gui/oven_control/config.cpp
+++ b/app/gui/oven_control/config.cpp
@@ -153,12 +153,12 @@ bool Config::saveConfig(void){
 }
 
 bool Config::loadConfig(){
-    char buff[sizeof(config_lists)+1];
+    uint8_t buff[sizeof(config_lists)+1];
     qint64 readlen;
     QFile file(CONFIG_FILE_NAME);
     initConfig();
     if(file.open(QIODevice::ReadOnly)){
-        readlen = file.read(buff,sizeof(config_lists)+1);
+        readlen = file.read((char *) buff,sizeof(config_lists)+1);
         file.close();
         if(readlen != (sizeof(configlist)+1)){
             //File size is wrong. apply default config value & save default value;
@@ -166,7 +166,7 @@ bool Config::loadConfig(){
             saveConfig();
             return false;
         }
-        if((unsigned char) buff[sizeof(config_lists)] ==0x9c){
+        if (buff[sizeof(config_lists)] ==0x9c){
             memcpy(configlist.data,buff,sizeof(config_lists));
             qDebug() << "loading config file success";
         }
diff --git a/app/gui/oven_control/fileprocessdlg.cpp b/app/gui/oven_control/fileprocessdlg.cpp
index e1f5781..9a2cf8b 100644
--- a/app/gui/oven_control/fileprocessdlg.cpp
+++ b/app/gui/oven_control/fileprocessdlg.cpp
@@ -658,7 +658,7 @@ void FileProcessDlg::configDownload(){
 }
 
 void FileProcessDlg::configUpload(){
-    char buff[sizeof(config_lists)+1];
+    uint8_t buff[sizeof(config_lists)+1];
     qint64 readlen;
     QString strUsbPath;
     QString strSrcPath;
@@ -668,7 +668,7 @@ void FileProcessDlg::configUpload(){
         QFile srcFile(strSrcPath);
         //Check Source File is valid this machine
         if(srcFile.open(QIODevice::ReadOnly)){
-            readlen = srcFile.read(buff,sizeof(config_lists)+1);
+            readlen = srcFile.read((char *) buff,sizeof(config_lists)+1);
             srcFile.close();
             if(readlen != (sizeof(config_lists)+1)) {
                 qDebug() << "SRC config.ini file size wrong";
@@ -676,13 +676,13 @@ void FileProcessDlg::configUpload(){
                 QTimer::singleShot(1000,this,SLOT(close()));
                 return;
             }
-            if((unsigned char) buff[sizeof(config_lists)] != 0x9C){
+            if(buff[sizeof(config_lists)] != 0x9C){
                 qDebug() << "SRC config.ini file check fail";
                 ui->ctrLbRemainTime->setText(tr("설정 업로드에 실패하였습니다."));
                 QTimer::singleShot(1000,this,SLOT(close()));
                 return;
             }
-            cfg->copyConfigArea(buff);
+            cfg->copyConfigArea((char *) buff);
             cfg->saveConfig();
             cfg->applyConfig();
         }