Add calendar by URL to Google Calendar Failing Again

I read the previous discussion and resolution regarding this problem this problem, which apparently occurred about a year ago. I am having the same problem today. I suspect the problem has come back again. I am using the example provided by zoho. The iCal url posted in Google is as follows:
https://creatorexport.zoho.com/acalver/mycal/ical/CALDATA_View/DTSTART=STARTS&DTEND=ENDS&SUMMARY=TITLE&DESCRIPTION=DETAILS&ZC_FULL_DAY_EVENT_VAR=ALLDAY

Google returns the error:
The address that you provided did not contain a calendar in a valid iCal or GData format.