You can change the e-mail address for receiving the two-step verification code required for logging in to cybozu.com Store.
The steps are as follows.

1. Log in to cybozu.com Store.

2. Click the e-mail address at the upper right of the screen and then select Account Settings from the drop-down list.
   

3. Click Change in the Two-Step Verification section.

4. In the Email input field, enter an e-mail address to which a verification code is sent.
   

5. Click Send.
   An e-mail that contains a verification code is sent to the specified e-mail address.
   

6. Check the verification code (a 6-digit number) in the e-mail whose subject is "[cybozu.com Store] Security Verification Code".

7. Go back to the cybozu.com Store screen.

8. Enter the verification code into the Verification Code field and click Verify.

9. Click Save.