Some of my drawing, assembly, and part files will not open and I get the error " cannot open future version". The assembly and all associated part files opened just fine one day, and the next morning they would not open. SW06 sp5.0 is installed while SW07 has never touched any of the machines that have access to these now unopenable files. Lucily I was able to recover the fies by opening the drawings in eDrawings and recreating them in a new part, however I am still baffled my this problem. Does anyone have any idea how or why this happened?