ORA-03137: Malformed TTC Packet From Client Rejected: [kpoal8Check-3] 
(Doc ID 2267564.1)
Last updated on FEBRUARY 08, 2019
Applies to:Oracle Data Provider for .NET - Version 126.96.36.199 and later
Microsoft Windows (32-bit)
Microsoft Windows x64 (64-bit)
After upgrading Oracle client from 188.8.131.52.0 to 184.108.40.206.0, .NET application which is using ODP.NET Managed driver to connect Oracle database is throwing the error as below:
The error occurs when a query is executed against the Oracle database from .NET application. Same query works fine if it is executed from SQL*PLUS environment.
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