I've modified the DSN names since running the install clist and now it appears that Netmaster is looking for the OLD DSN names.
When NetMaster starts up with a blank VFS file (and no INI file), Netmaster uses DSNQLCL, DSNQLNV and the DSNQSHR parameters defined in the RUNSYSIN member to create the DSN names.
These values are then written to the VFS DSN.
On the next restart of the region, since the VFS is not blank, NetMaster will use the values in the VFS DSN and NOT the values defined in the RUNSYSIN.
So, in this case, if the DSNQLCL, DSNQLNV and the DSNQSHR were not correct in the first startup, it is the OLD DSNs that were written to the VFS file.
To get around this, ensure that the defined DSNs match the DSNQ values in the RUNSYSIN.
Set the INIRESET parameter from NO to YES (PPREF='INIRESET=YES') in the RUNSYSIN and then restart the region.
NetMaster will treat the VFS as if it is BLANK and then will use the DSNQ defined in the RUNSYSIN to overwrite the values in the VFS file.
Once the region is started successfully, set the value back to NO. The next time the NetMaster region is started, it will read the VFS file with the corrected dataset names.