ris and other formats not importing into 7.7.1 for PC

Since about 10 days ago *.ris (and other files e.g. .bib) are not importing successfully into Endnote 7.7.1  (also true in 7.7.0, I was hoping the update would solve).  Instead of importing automatically, as before, I now get the dialogue box for “Choose An Import Filtre” but when I choose the correct one, the reference is not imported. 

OS = Win 8.1



Can you attach a few sample records from the .ris text file? Were you using the Refman RIS import filter?