diff --git a/DockerCPU.md b/DockerCPU.md
index 8c368b4..d66cdfd 100644
--- a/DockerCPU.md
+++ b/DockerCPU.md
@@ -27,6 +27,7 @@ http://(deepfacelab-cpu or 127.0.0.1):8888/?token=your token
 
 ```
 $ docker exec -it deepfacelab-cpu bash
+$ cd ../srv/
 ```
 
 ### 5. Use jupyter in deepfacelab-cpu bash
@@ -56,3 +57,17 @@ $ cd ../srv/
 $ chmod +x main.sh
 $ ./main.sh
 ```
+
+### some error
+
+#### localization.py system_locale is NoneType
+
+```
+# system_locale may be nil
+system_language = system_locale[0:2] if system_locale is not None else "en"
+```
+
+####  NVML Shared Library Not Found
+
+[Install NVIDIA Driver](http://www.linuxandubuntu.com/home/how-to-install-latest-nvidia-drivers-in-linux)
+[安装N卡驱动](https://linuxstory.org/how-to-install-latest-nvidia-drivers-in-linux/)
diff --git a/Dockerfile.cpu b/Dockerfile.cpu
index d477c13..e94c86f 100644
--- a/Dockerfile.cpu
+++ b/Dockerfile.cpu
@@ -2,6 +2,7 @@ FROM tensorflow/tensorflow:latest-py3
 
 RUN apt-get update -qq -y \
  && apt-get install -y libsm6 libxrender1 libxext-dev python3-tk\
+ && apt-get install -y ffmpeg \
  && apt-get install -y git \
  && apt-get clean \
  && rm -rf /var/lib/apt/lists/*
diff --git a/localization/localization.py b/localization/localization.py
index 4ccd9c8..d15be0b 100644
--- a/localization/localization.py
+++ b/localization/localization.py
@@ -2,7 +2,8 @@
 import locale
 
 system_locale = locale.getdefaultlocale()[0]
-system_language = system_locale[0:2]
+# system_locale may be nil
+system_language = system_locale[0:2] if system_locale is not None else "en"
 
 windows_font_name_map = {
     'en' : 'cour',