Once we go to Utilities -> User Tools -> Euro Code Load Combination Generator and click Generate Combinations, a warning message 'Warning - Both Permanent and Variable case are required' appears
Whenever one uses the Euro Code Load Combination Generator in STAAD.Pro, there are few conditions which must be satisfied in the STAAD.Pro model:
1) Make sure that each primary load case has its Loading Type set to an appropriate Category. I.e. for Dead Load Case set its Loading Type from None to Dead:
2) Make sure that Permanent and Variable Categories are properly set for each Load Type in the Euro Code Load Combination Generator:
3) Make sure that only one STAAD.Pro copy is opened when your run the Euro Code Load Combination Generator as this generator is based on the OpenSTAAD macro, which can properly work with only one STAAD.Pro model at a time.