Get configuration in assembly for old files

I'm using solidworks 2014.

I traversing assembly file that was created in the 2007 version. Get ModelDoc from Component2.

When I try to GetConfigurationByName() i've got COM error BAD_INDEX

This way works fine in current version assembly.

Is there any options to get gonfigurations for old files without saving assembly in new version?

SolidworksApi macros