diff --git a/app/gui/oven_control/config.cpp b/app/gui/oven_control/config.cpp
index d70b4aa..e6692f1 100644
--- a/app/gui/oven_control/config.cpp
+++ b/app/gui/oven_control/config.cpp
@@ -166,7 +166,7 @@ bool Config::loadConfig(){
             saveConfig();
             return false;
         }
-        if(buff[sizeof(config_lists)] ==0x9c){
+        if((unsigned char) 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 e9cf108..e1f5781 100644
--- a/app/gui/oven_control/fileprocessdlg.cpp
+++ b/app/gui/oven_control/fileprocessdlg.cpp
@@ -676,7 +676,7 @@ void FileProcessDlg::configUpload(){
                 QTimer::singleShot(1000,this,SLOT(close()));
                 return;
             }
-            if(buff[sizeof(config_lists)] != 0x9C){
+            if((unsigned char) 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()));