Opening a CATIA Version 4 Session in CATIA Version 5

This task shows you how to open a CATIA Version 4 Session in CATIA Version 5 on Windows or Unix.

This procedure allows you to translate V4 data (document structure) into V5 Format. Opening a CATIA V4 session generates a CATIA V5 CATProduct. This CATProduct contains the .model documents linked to the .session document.

A V4 Session document is a document structure containing several CATIA V4 models. If you open a V4 Session in CATIA V5, it is converted into a CATProduct. The models contained in the Session are automatically transferred into the CATProduct.

The impacts of opening a V4 Session in CATIA V5:

  • V4 Session => CATProduct
  • a V4 Session referencing Models => a CATProduct containing several Models
If you encounter any problems to open a V4 Session, please refer to Opening a V4 Session referencing CDM Models.
Only V4 Sessions saved "References only" can be read in CATIA V5.
  1. Click the Open icon or select the File -> Open... command.

  2. In the File Selection box, select the file location.

  3. In the "Files of type" list and select session as document type.

  4. Select the .session document of your choice and click OK.
    In our example the Session document looks like this in CATIA V5:

V4 Session documents containing models that are stored in databases can be opened in CATIA V5.
  1. Before opening the .session document, you need to make a connection between CATIA V5 and the databases (VPM, CDMA) in which the .models are stored.

For more information about:

  • interoperability between CATIA V5 and VPM, please refer to CATIA V5 / ENOVIA VMP Interoperability in VPM User Guide.

  • interoperability between CATIA V5 and CDMA, please read Using CDMA Data in a CATIA V5 Assembly (on UNIX only) in VPM User Guide.

  1. You also need to customize Document settings: Select the Tools->Options... command and the General category of the Options Tree, and click the Document tab. The ENOVIA VPM Database option must be active (Yes) and click OK to close the dialog box.

    The result in CATIA V5 is the same: the CATProduct contains the .models documents. It keeps its links with the models referenced in the session and stored in the databases.

V4 Session documents can be accessed from Windows with the http protocol. Make sure that an http server has been installed on the machine where the V4 data is stored.

The address to be specified should look like this: http://UNIXserver:port/V4datalocation.

If the links on the models are unresolved, the following dialog box appears :


Use the Search Order environment to specify the directories in which your linked documents are saved. For more information about the Search order environment, refer to Document in CATIA - Infrastructure User's Guide.

If CATIA Version 4 Session has been saved with a DLName (for instance, SESSION_DIR), and not with an UNIX path, you can specify the DLName into the Search Order list.

For more information about saving a .session document in a DLName environment, read Saving CATIA Version 5 CATProducts As CATIA Version 4 Sessions.

You can also convert a .session document into CATIA V5 in Batch mode. As a consequence, the V4 Session is converted into a CATProduct and the CATProducts contained in the Session are converted into CATProducts or CATParts.

You can convert a .session referencing Models stored in a database into CATIA V5 in Batch mode.

For more information about this type of conversion, refer to Converting a Version 4 Session into Version 5 in Batch Mode.