CNCat 4.2 User Manual
Installing CNCat 4.x over 4.0 and Higher
Save the backup copy of the database. To do this, export data from the old version into the XML-file (Administration – Settings – Export).
Copy new version files over the old files. Run the installation (see paragraph Installation).
While installing, you will be prompted to upgrade the old version. Select one of the methods: update the already installed version or delete program tables and install new version (see Update Old Version figure). In the latter case all the data will be deleted.