Problem opening VCF files on tf300
In this case an OS upgrade solved the issue.

For someone in a similar situation without an OS upgrade (or other fix) in sight, it might be worth taking a look at VCard Manager (which claims to be able to open all types of VCards) or Contacts VCF, which says to open any .vcf file:

 
VCard Manager and Contacts VCF (source: Google Play; click images for larger variants)