Using a Keio mail address with a normal Gmail account

After May 30, 2022, it will no longer be possible to set "Allow less secure apps" due to Google's system change. In addition, logging in using only user name and password including "password for email software" will also be restricted.
[Reference] Insecure apps and Google Account
As a result, you will no longer be able to use the method described here for sending messages with a Keio Mail address as the sender.

The following is an example of setting when you wish to receive email on Keio mail with a normal Gmail account or send email from a Keio mail address.
Please perform both Step 1 and Step 2.

Step 1: Setting to receive email by Keio mail

Login to Keio mail and do setting to add the normal Gmail account's email address to the forwarding addresses. For setting method, see "Automatically forwarding emails".
If you have already done forwarding settings, advance directly to Step 2.

Step 2: Setting to permit sending from a Keio mail's address

1. Log into normal Gmail. Look here for the method.
   

2. Click on the [Setting (Gear) icon] > [See all settings] displayed in the upper right of the screen.
   
   
   

3. Click the [Accounts] tab after the setting screen has opened.
   
   
   

4. Click [Add email address] in the [Name:] Column.
   (If there is already a Keio mail address in [Name:], click [Edit information] displayed to the right.)
   
   
   

5. After the email address addition screen has opened, enter the email address and click [Next Step]. Email address: Enter Keio mail email address.
   (If there is already a Keio mail email address entered in [Mail Address], click [Next Step])
   
   
   

6. "Verify our email address" is displayed, click on "Send Verification" button.
   
   
   
   

7. Email containing the authentication code will be sent to Keio mail, so confirm the authentication code.
   
   
   

8. Enter the authentication code and click [Confirm] on the normal Gmail side.
   
   
   

9. Confirm that the email address was added to the [Name:] column.
   
   
   

This completes the procedures.

If it fails, please set again [permission] of [Authorize] setting of [Authorize a low safety application] and check again.

When sending email using a Keio mail address, please change the [From:] address to the Keio mail address, then send it.
For method of changing the [From:] refer to the Google site: "Change the "From" address when replying or forwarding".