Issue with auto-generated usernames causing backend error when changing password

Hello WooCommerce team,

Recently (not sure if from the latest WooCommerce update or earlier), I noticed an issue with automatically generated usernames when customers create an account during checkout.

• When WooCommerce auto-creates the account (based on name/email at checkout), the username is generated with a dot (.) or similar.
• Later, when I go to WordPress backend → Users → Edit user → Change password, it always shows the error message:

“This username is not allowed. Only ‘a-z’, ‘0-9’, ‘-’, ‘_’, and ‘.’ are permitted.”

• However, if I manually create a user from the backend with the exact same username (including dot), there is no problem at all. The account works normally, and I can change the password without error.

This looks like WooCommerce’s account auto-generation logic is producing usernames that are technically valid, but not passing the validation check in the backend when editing.

I have attached screenshots to show: A user auto-created during checkout (fails when editing password): https://drive.google.com/drive/folders/1BC_ozxv9qBIEEiSDysiyPfZRshfBLErl?usp=sharing

Steps to Reproduce:

1. Go to WooCommerce → Settings → Accounts & Privacy, enable “Allow customers to create an account during checkout.”
2. Go to checkout, enter name and email → let WooCommerce auto-generate the account.
3. After order is placed, go to WordPress Admin → Users → Edit that user.
4. Try to change the password and save → error appears: “This username is not allowed. Only ‘a-z’, ‘0-9’, ‘-’, ‘_’, and ‘.’ are permitted.”

Expected behavior:

• Username generated by WooCommerce should fully comply with WordPress username rules, and backend should allow password change without errors.

Actual behavior:

• WooCommerce generates usernames that appear valid but are rejected in backend user profile editing.

Steps to Reproduce:

1. Go to WooCommerce → Settings → Accounts & Privacy, enable “Allow customers to create an account during checkout.”
2. Go to checkout, enter name and email → let WooCommerce auto-generate the account.
3. After order is placed, go to WordPress Admin → Users → Edit that user.
4. Try to change the password and save → error appears: “This username is not allowed. Only ‘a-z’, ‘0-9’, ‘-’, ‘_’, and ‘.’ are permitted.”

Expected behavior:

• Username generated by WooCommerce should fully comply with WordPress username rules, and backend should allow password change without errors.

Actual behavior:

• WooCommerce generates usernames that appear valid but are rejected in backend user profile editing.

Could you please check if this is a bug in WooCommerce’s user creation/validation process?

Thank you for your help!

• This topic was modified 7 months ago by chibilovespurple.
• This topic was modified 7 months ago by chibilovespurple.

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