To users of normal Gmail services

This page reports questions frequently asked by users of normal Gmail services when they use Keio mail, and answers to these questions.

After I log in to Keio mail, normal Gmail service opens.

Sign out of the opened Gmail, and log in to Keio mail once more.
You can switch between normal Gmail service and Keio mail on your Web browser. For details, see "Account switching operation method".
* The cause of this phenomenon is not the fact that the normal Gmail service (@gmail.com) and Keio mail (@keio.jp) accounts are integrated.

I want to receive emails of Keio mail with the normal Gmail service and send emails with the Keio mail address as the sender

On the Keio mail side, you can set email forwarding and make a setting so that you can send emails using the Keio mail address as the sender. For the setting method, refer to "Using a Keio mail address with a normal Gmail account".

Until now, I have sent emails from normal Gmail service with the Keio mail address as the sender, but cannot do that now

The migration of the Keio mail system requires you to change the contents of the settings of the normal Gmail service. Make the setting referring to "Using a Keio mail address with a normal Gmail account".

When I log into normal Google, "Account Renewal is Necessary." is displayed

When logging into normal Google, it confirms that it occurs in a case where an ID name identical to that of Keio ID is used. Respond referring to "Method of responding when "It is necessary to update your account" is displayed".

Look here for questions often asked to use Keio mail and Google Apps.
FAQ for Google Apps for Education