diff --git a/packages/app-store/googlecalendar/lib/CalendarService.ts b/packages/app-store/googlecalendar/lib/CalendarService.ts
index 60c97c4b6b..746fd4c902 100644
--- a/packages/app-store/googlecalendar/lib/CalendarService.ts
+++ b/packages/app-store/googlecalendar/lib/CalendarService.ts
@@ -58,7 +58,20 @@ export default class GoogleCalendarService implements Calendar {
         });
         myGoogleAuth.setCredentials(googleCredentials);
       } catch (err) {
-        this.log.error("Error refreshing google token", err);
+        let message;
+        if (err instanceof Error) message = err.message;
+        else message = String(err);
+        // if not invalid_grant, default behaviour (which admittedly isn't great)
+        if (message !== "invalid_grant") return myGoogleAuth;
+        // when the error is invalid grant, it's unrecoverable and the credential marked invalid.
+        // TODO: Evaluate bubbling up and handling this in the CalendarManager. IMO this should be done
+        //       but this is a bigger refactor.
+        await prisma.credential.update({
+          where: { id: credential.id },
+          data: {
+            invalid: true,
+          },
+        });
       }
       return myGoogleAuth;
     };
diff --git a/packages/core/getCalendarsEvents.ts b/packages/core/getCalendarsEvents.ts
index b00bdc674d..21103a27ff 100644
--- a/packages/core/getCalendarsEvents.ts
+++ b/packages/core/getCalendarsEvents.ts
@@ -11,7 +11,10 @@ const getCalendarsEvents = async (
   dateTo: string,
   selectedCalendars: SelectedCalendar[]
 ): Promise<EventBusyDate[][]> => {
-  const calendarCredentials = withCredentials.filter((credential) => credential.type.endsWith("_calendar"));
+  const calendarCredentials = withCredentials
+    .filter((credential) => credential.type.endsWith("_calendar"))
+    // filter out invalid credentials - these won't work.
+    .filter((credential) => !credential.invalid);
   const calendars = await Promise.all(calendarCredentials.map((credential) => getCalendar(credential)));
   performance.mark("getBusyCalendarTimesStart");
   const results = calendars.map(async (c, i) => {