--- title: Google Calendar "Unable to launch event" - caused by... description: Google Calendar throws an 'Unable to launch event' error when importing .ics files that are missing the DTSTAMP property, which is required by the iCalendar... canonical: https://daily.dev/posts/google-calendar-unable-to-launch-event---caused-by-missing-dtstamp-zmsskezyo twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Google Calendar "Unable to launch event" - caused by missing DTSTAMP | daily.dev og:description: Google Calendar throws an 'Unable to launch event' error when importing .ics files that are missing the DTSTAMP property, which is required by the iCalendar... og:url: https://daily.dev/posts/google-calendar-unable-to-launch-event---caused-by-missing-dtstamp-zmsskezyo og:image: https://api.daily.dev/og/posts/zMSSKezYo.png og:image:alt: Google Calendar "Unable to launch event" - caused by missing DTSTAMP og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Google Calendar "Unable to launch event" - caused by missing DTSTAMP **[Terence Eden](https://daily.dev/sources/shkspr)** · 2 min read · 0 upvotes · 0 comments ## Summary Google Calendar throws an 'Unable to launch event' error when importing .ics files that are missing the DTSTAMP property, which is required by the iCalendar RFC 5545 specification. The fix is straightforward: add a DTSTAMP field to the VEVENT block. Broken files tend to work on iOS and some Android calendars but consistently fail on Google Calendar. Google's own iCal documentation is vague and doesn't specify required event properties, and there's no easy way to report the bug directly to Google. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### Why does Google Calendar show 'Unable to launch event' when importing an .ics file? The error occurs because the VEVENT block is missing the required DTSTAMP property. RFC 5545 mandates that DTSTAMP must be included in VEVENT, VTODO, VJOURNAL, or VFREEBUSY components, but many calendar invites (such as delivery notifications) omit it. Adding a DTSTAMP line with a timestamp, such as DTSTAMP:20260713T093000Z, resolves the import failure in Google Calendar. _Debugging finicky calendar integrations gets easier with technical writeups like this surfaced on daily.dev._ ### Does a broken .ics file without DTSTAMP work on iOS but fail on Google Calendar? Yes, informal testing found that .ics files missing the DTSTAMP property generally work on iOS devices and on some Android calendar apps, but always fail to import on Google Calendar. This inconsistency across calendar clients means senders of automated invites (like delivery notifications) may not notice the bug unless a recipient specifically uses Google Calendar. _Cross-platform quirks like this are worth tracking for anyone shipping calendar features, and daily.dev helps surface them._ ## Similar posts on daily.dev - ["iT woRKs BeTter in THe aPp\!\!"](https://daily.dev/posts/it-works-better-in-the-app--wlvi0bcsg) · Terence Eden · 0 upvotes · 0 comments - [In the Zone](https://daily.dev/posts/in-the-zone-tpzp94dpf) · The Daily WTF · 0 upvotes · 0 comments - [How I fell in love with calendar.txt](https://daily.dev/posts/how-i-fell-in-love-with-calendar-txt-rpr9ytnob) · Lobsters · 118 upvotes · 12 comments - [Exploiting Google Gemini to Abuse Calendar Invites Illustrates AI Threats](https://daily.dev/posts/exploiting-google-gemini-to-abuse-calendar-invites-illustrates-ai-threats-j6bbmlvcw) · Security Boulevard · 0 upvotes · 0 comments --- Tags: [#google](https://daily.dev/tags/google) [View this post on daily.dev](https://daily.dev/posts/google-calendar-unable-to-launch-event---caused-by-missing-dtstamp-zmsskezyo) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Google Calendar \"Unable to launch event\" - caused by missing DTSTAMP","url":"https://daily.dev/posts/google-calendar-unable-to-launch-event---caused-by-missing-dtstamp-zmsskezyo","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/google-calendar-unable-to-launch-event---caused-by-missing-dtstamp-zmsskezyo"},"datePublished":"2026-07-28T11:37:17.752Z","dateModified":"2026-09-14T09:30:02.508Z","description":"Google Calendar throws an 'Unable to launch event' error when importing .ics files that are missing the DTSTAMP property, which is required by the iCalendar...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/e64df2a4bf95cb51ace1f56fdd2baf84?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/e64df2a4bf95cb51ace1f56fdd2baf84?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"Terence Eden","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Terence Eden","logo":"https://media.daily.dev/image/upload/s--nhylgPuf--/f_auto,q_auto/v1774964413/logos/shkspr?_a=BAMAMiWQ0","url":"https://daily.dev/sources/shkspr"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/google-calendar-unable-to-launch-event---caused-by-missing-dtstamp-zmsskezyo","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"google","timeRequired":"PT2M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Terence Eden","item":"https://daily.dev/sources/shkspr"},{"@type":"ListItem","position":3,"name":"Google Calendar \"Unable to launch event\" - caused by missing DTSTAMP"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/google-calendar-unable-to-launch-event---caused-by-missing-dtstamp-zmsskezyo#faq","mainEntity":[{"@type":"Question","name":"Why does Google Calendar show 'Unable to launch event' when importing an .ics file?","acceptedAnswer":{"@type":"Answer","text":"The error occurs because the VEVENT block is missing the required DTSTAMP property. RFC 5545 mandates that DTSTAMP must be included in VEVENT, VTODO, VJOURNAL, or VFREEBUSY components, but many calendar invites (such as delivery notifications) omit it. Adding a DTSTAMP line with a timestamp, such as DTSTAMP:20260713T093000Z, resolves the import failure in Google Calendar. Debugging finicky calendar integrations gets easier with technical writeups like this surfaced on daily.dev."}},{"@type":"Question","name":"Does a broken .ics file without DTSTAMP work on iOS but fail on Google Calendar?","acceptedAnswer":{"@type":"Answer","text":"Yes, informal testing found that .ics files missing the DTSTAMP property generally work on iOS devices and on some Android calendar apps, but always fail to import on Google Calendar. This inconsistency across calendar clients means senders of automated invites (like delivery notifications) may not notice the bug unless a recipient specifically uses Google Calendar. Cross-platform quirks like this are worth tracking for anyone shipping calendar features, and daily.dev helps surface them."}}]} ```