First I would like to say that I think your Zoho Projects API is very straight-forward and has pretty good documentation. However, your error code descriptions are quite terrible. Repeating the error message as the description is NOT a description. 

I've been using Zoho APi's for about 2 years now. Lot's of work with Zoho Creator and Zoho CRM. I'm a little new to Zoho Projects.

I keep getting the same "General Error" 6500 ON EVERY CALL. My apikey and ticket are set just fine. But I still get this error. I've tried two separate accounts/portals with no luck. How can I debug this or is there something wrong on your end? Thanks!