After installing the smtest tool in sdk version 12.52SP1 with working hco and agent/shared secret combinations getting the following in the smps.log
[LogMessage:ERROR:[sm-Server-01070] Failed handshake with xxx.xxx.xxx.xxx:yyyy]
Was working with previous version of SM test tool
You should check that you do not have multiple version of ETPKI packages installed on your box and install the one provided with the SDK.
Check the following registry for installed libraries: