2013 file will not open in 2013 software. File extension is .tax2013. if clicked says it is a pdf file. If opened from TT, it will not load. How do I get my file back?

this problem exists for 2013-14. All other TT files are shown as "turbotax document" and load. But for these years my saved files are listed as Adobe PDF files... even thought the file extension is *.tax2013 and *.tax2014. How do I "relabel" these files as TurboTax file documents?  Very strange!