I’m guessing this is caused by a compatibility issue between the 2 HVR versions (4.7.3 and 5.2.1) that you are using. There have been major changes between the 4.7 and 5 versions.
Do you have a strong reason to use this mix of versions? Even if you don’t want to upgrade the source or target versions (e.g. because they are used by other channels) it is still possible to have a second HVR installation (with the newer version) installed on that machine listening on a different port number; That would be done as follows:
You would just choose different values from HVR_HOME and HVR_CONFIG; install the new software in the new HVR_HOME directory.
Start a new hvrremotelistener (or inetd configuration) listening on a different port.
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