I insert the Survey in an article with the plugin [loadposition opros1].
Survey ends normally if the user is not logged on the website.
If the survey  is a registered user can not be complete. Displays an error after you click Continue: "An error occurred while processing your request. Please try again."

The properties of the survey removed all restrictions on unique users.

Please, help solve this problem

P.S. I turned on option debug. I'v error message "An error occurred while processing your request. Please try again.| Error: 103 - rid=101 key=O4LCq3skBjCTm9KiGTH5zvd7SJZvDo0S userid=304"

P.S. P.S.  Now everything works. Issue closed. Thanks