http://nxway.blogspot.ca/2007/10/prt-extension-and-multiple-nx-versions.html
To open prt files with NX 7.5:
Change HKEY_CLASSES_ROOTUGpartfileshellopencommand to
"C:Program FilesUGSNX 7.5UGIIugs_router.exe" -version=V25.5 -ug -use_file_dir "%1"
http://nxway.blogspot.ca/2007/10/prt-extension-and-multiple-nx-versions.html
To open prt files with NX 7.5:
Change HKEY_CLASSES_ROOTUGpartfileshellopencommand to
"C:Program FilesUGSNX 7.5UGIIugs_router.exe" -version=V25.5 -ug -use_file_dir "%1"