I have a calendar view in one of my bases.  I went to share view, sync to an external calendar and copied the link.  I sent this link to a user via text.  I had the user right-click and select copy from the text message.  I then had her go into apple calendar, calendars, add calendar, add subscription calendar, paste the URL in the subscription URL field and click on subscribe.  She then gets the message "Validatioin failed.  Please edit the URL and try again"  I tried the same steps at the same time she did in my own calendar and it worked fine.  What could the issue be?