Configuring the Creo View Interference Engine > Working with the Creo View Interference Engine > Changing the Reporting of Interferences of Unavailable Volumes
  
Changing the Reporting of Interferences of Unavailable Volumes
In cases where the interference volume is not calculated, Unavailable is returned. This applies to calculations made both in Accurate and Approximate modes. To avoid the creation of Unavailable instances and to scale down the size of the Interference reports, you can set the following environment variable.
set PVIEW_CLASH_NO_VOLUME=ignore—The interferences are not reported.
set PVIEW_CLASH_NO_VOLUME=contact—The interferences are categorized as Contacts.
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If you compare results that were created with different environment variables you should ensure that the results are suitable for your use.
If the environment variable is set to contact, and only Interference is calculated, interferences that are not calculated are not reported.