diff --git a/Dockerfile b/Dockerfile
index a040b64..36eb766 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -4,7 +4,7 @@ FROM ${LAB_IMAGE}
 RUN echo "install custom extensions"
 #RUN python3 -m pip install --upgrade pip setuptools wheel
 RUN pip install --extra-index-url https://git.sandbox.iuk.hdm-stuttgart.de/api/packages/grosse/pypi/simple jupyterlab-sandbox-theme
-RUN pip install --extra-index-url https://git.sandbox.iuk.hdm-stuttgart.de/api/packages/grosse/pypi/simple jupyterlab-sandbox-announcement
+RUN pip install --extra-index-url https://git.sandbox.iuk.hdm-stuttgart.de/api/packages/grosse/pypi/simple jupyterlab-sandbox-announcement==0.1.2
 #RUN pip install --extra-index-url https://git.sandbox.iuk.hdm-stuttgart.de/api/packages/grosse/pypi/simple jupyterlab-data-pool
 #RUN pip install --extra-index-url https://git.sandbox.iuk.hdm-stuttgart.de/api/packages/grosse/pypi/simple jupyterlab-training
 #RUN pip install --extra-index-url https://git.sandbox.iuk.hdm-stuttgart.de/api/packages/grosse/pypi/simple jupyterlab-synthetic-data