Subscribing from Zoho Calendar to to an ICS file on my computer is unsucessful.

Subscribing from Zoho Calendar to to an ICS file on my computer is unsucessful.

I created an ICS file with an online utility and downloaded it to my computer. I then tried to subscribe/import it in Zoho Calendar but was unsuccessful. I have attempted the following URLs so far:

C:\Users\XXXXX\Desktop\RaleighArea_Drag_Strips_September_2014.ics

file:///C:/Users/XXXXX/Desktop/RaleighArea_Drag_Strips_September_2014.ics

It appears that I may have to find a place to host the file online before it works. Do you have any suggestions? The file is attached with a TXT extension instead of ICS.