diff --git a/install/windows/build-wxs.py b/install/windows/build-wxs.py
index a1ee569..7ae4028 100644
--- a/install/windows/build-wxs.py
+++ b/install/windows/build-wxs.py
@@ -16,7 +16,7 @@ def build_data(base_path, path_prefix, dir_id, dir_name):
         data["component_id"] = "ApplicationFiles"
     else:
         data["component_id"] = "Component" + dir_id
-    data["component_guid"] = str(uuid.uuid4())
+    data["component_guid"] = str(uuid.uuid4()).upper()
 
     for entry in os.listdir(base_path):
         entry_path = os.path.join(base_path, entry)
@@ -118,7 +118,7 @@ def main():
         "Package",
         Name="Dangerzone",
         Manufacturer="Freedom of the Press Foundation",
-        UpgradeCode="12b9695c-965b-4be0-bc33-21274e809576",
+        UpgradeCode="12B9695C-965B-4BE0-BC33-21274E809576",
         Language="1033",
         Compressed="yes",
         Codepage="1252",
@@ -181,7 +181,7 @@ def main():
         programmenufolder_el,
         "Component",
         Id="ApplicationShortcuts",
-        Guid="539e7de8-a124-4c09-aa55-0dd516aad7bc",
+        Guid="539E7DE8-A124-4C09-AA55-0DD516AAD7BC",
     )
     ET.SubElement(
         shortcut_el,