diff --git a/spoolman/env.py b/spoolman/env.py
index 7fe8c3b..dbe0f8d 100644
--- a/spoolman/env.py
+++ b/spoolman/env.py
@@ -312,7 +312,10 @@ def get_build_date() -> Optional[datetime]:
     with build_file.open(encoding="utf-8") as f:
         for line in f:
             if line.startswith("BUILD_DATE="):
-                return datetime.fromisoformat(line.split("=")[1].strip())
+                try:
+                    return datetime.fromisoformat(line.split("=")[1].strip())
+                except ValueError:
+                    return None
     return None