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To connect to the environments, you can use your B2B owner account (from the B2B Users dashboard) on your BigCommerce store. When you add a user email id to the B2B Users section in the Control Panel, an email is sent to that id for a user to set the password for B2B access.
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When the email is received, set the password for the created B2B Edition account
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It is this user email id and password combination that allows for successful B2B connections for the respective environments.
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After entering the required details, click on the “Connect “Connect” button to connect to the environment.
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IMPORTANT: You need to see the ‘Connected’ button for the B2B entities to show correctly in the Bulk Content Migration tab.
A store environment with Bundle B2B support will be displayed under the Bulk Content Migration tab.
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For any connection issues countered:
While not mandatory, it is sometimes helpful to have the B2B user also set as a BigCommerce Control panel user (e.g. user alphademo set as both a B2B user and a BigCommerce Control Panel user with the same email id). However, please remember that the B2B user credentials are separate to the BigCommerce Control panel user. Only the B2B password set by the automated email is used for B2B authentication.
You can try to delete and recreate the B2B user on the B2B portal, set the password and try again
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