I use Google Gmail for a number of my email accounts, both company an personal.
I have noticed with surprise that some of my Gmail accounts have the new format, where my emails are grouped according to whether it is a Forum, Social or Promotion at the top tabs.
However, there is my one account that I use often that has not been migrated to this new version. I would like to use it as my email is very cluttered and confusing without it.
How do I upgrade to it?