I don’t know if this is related or a different issue, but i’ve been having problems with Calendar on my v4.1.2 deployment also. The same ics file works fine with my older 3.3.7 deployment.
The calendar is an Office 365 shared calendar.
In the logs on 4.1.2, i get the following:
downloadIcs: Unable to get feed: cURL error 60: SSL certificate problem: unable to get local issuer certificate (see https://curl.haxx.se/libcurl/c/libcurl-errors.html) for https://outlook.office365.com/owa/calendar/.../reachcalendar.ics
That error code (60) is ( libcurl - Error Codes):
CURLE_PEER_FAILED_VERIFICATION (60)
The remote server's SSL certificate or SSH fingerprint was deemed not OK. This error code has been unified with CURLE_SSL_CACERT since 7.62.0. Its previous value was 51.
After that, i get:
iscProvider: fetchData: Unable to download feed
and
The iCal provided is not valid, please choose a valid feed
I found a ticket relating to that error, but having played with permissions on the ca-certs folder, i can’t replicate their fix. cURL error 60: SSL certificate problem - Get Help - Xibo Community
I also found a post by @dan walking through updating CA root certificates for PHP ( Using Tickers, Forecast, Twitter and other external resources that make use of HTTPS connections - FAQ’s - Xibo Community ) and a follow-up talking about adding a SSL inspection certificate to that bundle ( Issues with weather (curl error 60) self signed cert - Get Help - Xibo Community ).
But no joy. I’ll keep pulling at this thread and see