Foundry376/Mailspring · error

EventHeader: Could not parse ICS data from calendar event: $

Error message

EventHeader: Could not parse ICS data from calendar event: ${e.message}

What it means

Warning in EventHeader's query subscription: a matching Event row was found in the database and its stored ics re-parsed, but parsing threw — the synced calendar event's ICS is corrupt or in a format the parser rejects. The component keeps the last good icsEvent state instead of crashing.

Source

Thrown at app/internal_packages/events/lib/event-header.tsx:108

        icsEvent: event,
        icsMethod: normalizedMethod as 'reply' | 'request' | 'cancel',
        icsOriginalData: data.toString(),
      });

      this._subscription = Rx.Observable.fromQuery(
        DatabaseStore.findBy<Event>(Event, {
          icsuid: event.uid,
          accountId: message.accountId,
        })
      ).subscribe((calEvent) => {
        if (!this._mounted || !calEvent) return;
        try {
          this.setState({
            icsEvent: CalendarUtils.parseICSString(calEvent.ics).event,
            icsOriginalData: calEvent.ics,
          });
        } catch (e) {
          console.warn(`EventHeader: Could not parse ICS data from calendar event: ${e.message}`);
        }
      });
    });
  }

  componentDidUpdate(prevProps: EventHeaderProps, prevState: EventHeaderState) {
    if (prevState.inflight) {
      this.setState({ inflight: undefined });
    }
  }

  render() {
    const { icsEvent, icsMethod } = this.state;
    if (!icsEvent || !icsEvent.startDate) {
      return null;
    }

    // Workaround to convert calendar invites sent out from Microsoft calendars to IANA timezones

View on GitHub (pinned to 648c685d60)

Solutions

1. Re-sync the calendar account so a fresh ICS is stored for the event
2. If persistent, the event was created with a non-standard ICS flavor; delete and recreate it

When it happens

Trigger: Thrown at app/internal_packages/events/lib/event-header.tsx:108 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of Foundry376/Mailspring@648c685d60 (2026-09-03). Data as JSON: /api/errors/098915ca4c403444. Report an issue: GitHub.