If you use any prefixes they are now defined on the server and not in the client.
Have you tried testing the odbc client via the pxpsql command line client or from other software like Excel? If it works there then you know the odbc driver is setup correctly and the issue is the linked server config.
Check out the documentation for our ODBC here:
https://manual.pvxplus.com/?odbc/pxplus_odbc.htmIn the tree view you can find configuration instructions, an FAQ, and details on the command line client and how to use it.
If you still have issues I suggest you ask for help through support. Make sure you include as much detail as possible including the serial number, ODBC DSN connection string, the PxPLus SQL Server conf file or screen shots from the PxPlus SQL Server Configuration app, and MS SQL Server linked table config screenshots.
Support is through the PxPlus reseller, unless you buy directly from PVX Plus Technologies in which case you can create a support ticket from the PVX Plus Technologies website.