Attempting to commission a Niagara G3 ENC-520 and an error indicates the nre core distribution files cannot be found on the local computer.
The distribution files are typically installed under the Niagara directory in \sw\3.5.34 (or other version number)
Niagara G3 all versions
The distribution files were not installed on the computer as the checkbox for
"This instance of TAC I/A Series Enterprise Network Server will be used as an installation tool"
was disabled (or NOT checked) during the installation process.
Re-install the Niagara G3 software version with the checkbox (described above) enabled.