Bing Ads has been on a steady track to sunset managed credentials by migrating all users to Microsoft accounts. These legacy credentials use username/password combinations to log into Bing Ads rather than an email/password combination. To ensure all our customers are getting the latest and greatest in security that Microsoft has to offer, with an authentication experience that has multi-factor authentication capabilities and uses the best fraud detection algorithms, we will cease support for managed credential sign-in across all Bing Ads entry points, including the API.
As of August 1st, 2018, all Bing Ads API Version 11 service calls with managed UserName and Password credentials will return an error. Bing Ads API Version 12 already does not accept the managed user credentials. To make this experience as smooth as possible, we encourage you to migrate to v12 ahead of the changes in August. For more details about authenticating with a Microsoft Account, see Authentication with OAuth.
If a user of your application is blocked from authenticating with their managed user credentials, they can sign in via the Web to migrate their managed credential to a Microsoft account. We are encouraging all users to migrate to a Microsoft account prior to August 1st to avoid interruptions to service. For more information on migration, please refer to the help documentation.
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