Banner, PeopleSoft, and Workday export feeds with missing VTIMEZONEs and broken RRULE syntax. We detect and repair 36+ RFC 5545 violations. Paste your feed URL to see exactly what's broken.
Paste the URL of your broken calendar feed
Paste your feed URL above to see specifically what's broken.
We've analyzed thousands of Canvas LMS calendar feeds. Here are the most common RFC 5545 violations we detect and repair automatically at the network edge.
Calendar feed lacks VTIMEZONE definition for non-UTC times
Impact
Events appear at wrong time on iOS/Android (typically 4-8 hours off)
How Lokr Fixes It
We inject RFC 5545-compliant VTIMEZONE blocks automatically
RFC 5545 §3.6.5 requires VTIMEZONE components for all non-UTC DATETIME values
DTSTAMP is more than 7 days old
Impact
Calendar clients may reject updates or fail cache invalidation
How Lokr Fixes It
We refresh DTSTAMP to current UTC time on every request
RFC 5545 §3.8.7.2 requires DTSTAMP to reflect last modification time
Recurrence rule has invalid syntax or unsupported values
Impact
Recurring events fail to repeat or show incorrect instances
How Lokr Fixes It
We sanitize RRULE syntax and normalize FREQ, BYDAY, UNTIL values
RFC 5545 §3.3.10 defines strict RRULE syntax requirements
Text fields contain invalid escape sequences like \t or \r
Impact
Text appears garbled or with literal backslashes
How Lokr Fixes It
We normalize to RFC 5545-compliant escape sequences (\n, \,, \;)
RFC 5545 §3.3.11 defines valid escape sequences for TEXT
VALARM component has syntax errors
Impact
Reminders fail to trigger or are ignored
How Lokr Fixes It
We fix VALARM syntax or remove malformed components
RFC 5545 §3.6.6 defines VALARM component structure
5
Total Error Types
1
Critical Errors
100%
Fixed Automatically
<15ms
Repair Latency
Integration with legacy systems like Canvas LMS requires infrastructure-level remediation to ensure mobile sync reliability.
Events often lack explicit time zone definitions, causing deadlines to shift when students travel or view on mobile.
14:00 GMT
09:00 EST
Canvas exports include massive amounts of historical data, causing sync timeouts on mobile networks.
Google Calendar updates from Canvas can take up to 24 hours. Lokr proxies this for near-instant refreshes.
We force-refresh the feed headers to bypass Google's 12-hour cache.
Log in to Canvas and click 'Calendar' in the global navigation.
Click the 'Calendar Feed' link in the bottom right corner.
Copy the URL provided in the dialog box.
Paste it into the Lokr test tool above.
Subscribe to the new Lokr link on your phone.
We don't sell to end-users. We build for the engineers and admins who have to keep the systems running.
"Ellucian Banner generates compliant ICS files for desktop, but they break on iOS. Lokr standardizes the output so students actually see their exam schedules."
James T.
University Registrar, Major State University
"Integrating Canvas was easy, but the calendar subscriptions were flaky. Lokr's proxy layer stabilized the Canvas feeds for over 40,000 students."
Elena R.
CIO, Private Research University
"We use Salesforce for alumni events. Lokr cleans the feed so alum on old Android devices still get the correct event times."
Marcus L.
Alumni Relations Tech Lead, Liberal Arts College
Canvas LMS is a critical component for these industries. See how Lokr provides infrastructure-grade calendar sync for each specific vertical.
Diagnose errors and test the fix instantly.
Fix one critical feed.
Department-wide infrastructure.
Organization-wide infrastructure.
Higher Education departments utilize the Standard plan to remediate SIS export errors.
Standardize your campus calendar infrastructure.
Contact Sales, we’ll set up your perfect feed today.
Stop fielding support tickets about broken calendars. Get a verified, RFC-compliant feed today.
Initialize a production Canvas LMS proxy environment with Zero-Persistence security.
Review technical standards across Higher Ed, Logistics, and Enterprise IT.
Step-by-step remediation for Canvas, Greenhouse, Ellucian, and PeopleSoft.