IFS Report Designer cannot connect – 400 Bad Request (Malformed Request) when accessing ReportDesigner ClientHandling projection (IFS Cloud 24R2)

I am trying to connect IFS Report Designer to IFS Cloud 24R2, but the connection fails with an HTTP 400 error.

Error Message

An unexpected ERROR occurred while trying to connect Xcom.ini.vldt.server.ServerException: Login succeeded. Accessing the projection 'ReportDesigner ClientHandling' resulted in an error. Reported error is (REQUEST_ERROR) Malformed Request. [HTTP/1.1 400 Bad Request]

Environment

• IFS Cloud Version: 24R2

• Report Designer Version: 200.3.0003

• Database User: IFSAPP

• IAM Client: IFS_REPORT_DESIGNER

IAM Client Configuration

• Enabled: On

• Public Client: On

• Service Accounts: Off

• Direct Access Grants: Off

Redirect / Allowed URLs

https://*****.ifscloud.com.tr/* http://localhost/*

Permissions

• All required permission sets are granted to:

  • IFSAPP

  • IFS_REPORT_DESIGNER

• IAM client is active and visible

Steps to Reproduce (Minimal Reproducible Example)

1. Open IFS Report Designer

2. Enter IFS Cloud URL and credentials

3. Login succeeds

4. Connection fails while accessing projection
   ReportDesigner ClientHandling

5. HTTP 400 Malformed Request error is returned

Expected Result

Report Designer should successfully connect and load the Report Designer environment.

Actual Result

Connection fails after login with HTTP 400 Bad Request.

Question

What could cause a 400 Malformed Request error when accessing the
ReportDesigner ClientHandling projection in IFS Cloud 24R2, even though:

• IAM client is active

• Permissions are granted

• Login succeeds?

Are there any version compatibility requirements, IAM settings, or IFS Cloud configuration steps specific to Report Designer in 24R2 that could cause this issue?