Error on ODBC call - Connection Open invalid instance

Hey experts,

when i try to access a repository from a local DS client the following error message shows up.

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the german part says: error on odbc-call<..>for data source <..> invalid connection.

I'm using SAP DS 4.2 SP03. However, when I try to access the repository from the client on the server it works fine.

Any ideas and thanks in advance.

Regards,

Eduard