I had a Google Plus business page where and I changed the ownership of the account to a new manager.
The Google Plus page had an associated email account that could be logged into just like any other Gmail account.
However, after the Google Plus page ownership was transferred, the password for Gmail account owned by the Google Plus page no longer applies. It says the password was recently changed. There was a link that says "Didn't change your password?", and I clicked through to that, and ended up on a message that says:
Password information
Please contact your account owner to reset your password or retrieve your username.
The new account owner is my personal Google account, but even though I can go to the Google Plus page and confirm that I am the owner, I can't see any options for changing the password on the Google plus business page.
How do I regain access to the Google Plus business page's Gmail interface now that the owner has changed?
Best Answer
It seems that after having transferred ownership of the Google+ business page, the previous password for the Gmail account associated with that business page is reset or something. I guess maybe the assumption is that if you transfer ownership, you don't want the old owner to have access, maybe?
In any case, turns out that you need to set a password for the Gmail account after changing ownership. To do so, you log in as the owner of the business page. You then go to that page's settings.
In the settings interface, you scroll down and you will hopefully see this:
Click on the "set up a password" button, and after that it should be self explanatory.
Took me a lot of of searching for me to figure this out. Hope it's helpful to someone.