3800266 - BAS cannot connect to server; preview requests fail and fiori generator cannot list odata services - Business Application Studio

On August 31, 2026, some Business Application Studio customers experienced issues when accessing SAP backend systems through configured destinations from their Dev Spaces.

Requests to the backend systems returned 403 errors, which prevented affected users from accessing backend systems and, in some cases, deploying applications through the destination connection.

Applications already deployed and running on Cloud Foundry were not affected and continued to operate normally.

Symptoms:

• Inability to connect from Business Application Studio (BAS) to the development server.
• Errors occur when querying after running a program locally in BAS or deploying an application to a server
• All data communication from BAS fails.
• The SAP Fiori Application Generator cannot retrieve the OData service list.
• When running apps in BAS preview, data requests fail with HTTP 403 errors.
• Backend requests via the destination return HTTP/1.1 401 Unauthorized.
• Deployment fails with a 403 error

• Business Application Studio (BAS)
• BTP, Cloud Foundry runtime and environment

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