diff --git a/Projects/CalDAV b/Projects/CalDAV
index a3af50c..469deb8 100644
--- a/Projects/CalDAV
+++ b/Projects/CalDAV
@@ -9,7 +9,7 @@ Calendaring software provides users with an
 electronic version of a calendar. Additionally, the software may provide an
 appointment book, address book, or contact list.
 
-We implemented a CalDAV server based on MirageOS.  
+We implemented a CalDAV server based on MirageOS.
 [CalDAV](https://en.wikipedia.org/wiki/CalDAV) is a calendaring extension to
 WebDAV, an HTTP-based protocol that allows to read, write and alter files, directories and file properties.
 
@@ -28,9 +28,9 @@ For iOS you need to add an account in the calendar app, select "other" and then
 Discovery of calendars happens automatically.
 
 If you use Thunderbird Lightning, you need to create a new calendar on the network, select CalDAV as remote calendar format, and enter a full calendar URL, e.g.
-`http://calendar.robur.io/calendars/<username>/calendar`.
+`https://calendar.robur.io/calendars/<username>/calendar`.
 
-If you use DAVdroid, you can enter the short URL like for MacOS.
+If you use DAVdroid, you can enter the short URL like for MacOS, but you need to append `/calendars`.
 Discovery of calendars happens automatically.
 
 ## How to host the calendar server yourself