namespace error while connecting to RSLinx OPC server with matlab

[ILC_H 2]

Hello PLC expert
i need your help. i want to use OPC communication and Matlab to read and write data from/to a Logix5561. A Topic is already configured on RSLinx. On my PC i installed MATLAB and i can connect to the OPC Server using Simulink opc Toolbox. My Problem occurs when i want to add Items, i receive a Simulink error saying Name space Browsing not avaible. and Matlab says could not retrieve name space for Server. Error was: StartItemId is not a branch in the Server Namespace

Additionaly i have RSView32 as an OPC Client too and although it is working fine, there is an error saying: OPC Error :Server the item is no longer available.

could the error in RSView32 be the root cause of my Problem ?

edit: I forgot to mention, that on Simulink opc read and opc wirte box have the Mention disabled in brace .

Edited 16 Jul 2020 by ILC_H
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