diff --git a/server/main-api/src/calendar/refresh.rs b/server/main-api/src/calendar/refresh.rs
index dcade422f..22ba82ad0 100644
--- a/server/main-api/src/calendar/refresh.rs
+++ b/server/main-api/src/calendar/refresh.rs
@@ -16,6 +16,13 @@ struct LocationKey {
     key: String,
 }
 pub async fn all_entries(pool: &PgPool) {
+    let client_id_invalid = std::env::var("CONNECTUM_OAUTH_CLIENT_ID").is_err();
+    let client_secret_invalid = std::env::var("CONNECTUM_OAUTH_CLIENT_SECRET").is_err();
+    if client_id_invalid || client_secret_invalid {
+        error!("Please make sure that CONNECTUM_OAUTH_CLIENT_ID and CONNECTUM_OAUTH_CLIENT_SECRET are valid to use calendar features");
+        return;
+    }
+
     let mut api = APIRequestor::from(pool);
     loop {
         let start = Instant::now();