What is the shelf life of Ultra Clear rice protein powder?
I suggest that you contact the manufacturer of the powder and ask them. You will get an answer that is specific to your product and possibly an explanation as to why the product is safe to use or not. Doing so will also help avoid any online speculation by others that may result in you becoming unnecessarily ill.

As for contacting the manufacturer, I believe that UltraClear is produced by Metagenics and you can contact them online here. If that doesn't work, you can call them toll-free (more information about calling them can be found at the online contact form).