HDM-4 Version 2.0 cannot open databases created with HDM-4 Version 1.3, however a software tool is included to enable the migration of existing data to the new data format. This topic is covered in the "Getting Started With HDM-4 Version 2.0" manual which is included with the software and is available as a free download. The introduction to the relevant section is copied below, but you should refer to the manual for further details.
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Using Existing Data with Version 2.0
Overview
There have been extensive changes in the handling and organisation of data, as well as the introduction of new functionality within HDM-4 Version 2.0. It is therefore not possible to directly use existing HDM-4 Version 1.x data. It is realised that the existing data stored in Version 1.x is valuable to an organisation and therefore a tool has been developed to aid the migration of this data into a format that can be used in Version 2.0.
The HDM-4 Data Migration Tool aims to take an existing HDM-4 Version 1.3 workspace and re-organise and reformat the data to conform to that required by HDM-4 Version 2.0. After running the HDM-4 Data Migration Tool the user should review the data to ensure its integrity prior to running an analysis and publishing the results. Due to the model changes that are included in HDM-4 Version 2.0 the user should pay particular attention to the calibration of the deterioration models and the works trigger conditions and effects.