What is my previous tax year file name

what is the file name of  my previous year tax, trying to carry forward the information 

thanks

Getting started

Hello,


The file name is going to depend on the company name so there is not much help I can provide with the name of the company, however I can tell you that if the previous years file was in a 2016 format the extension would be .GB6 if it was in a 2015 format the extension would be .GB5.