WLM 2012  on Win8 PC. Version 2012 (Build 16.4.3528.0331)

Export worked fine a month ago , but now it appears to run successfully, but ends immediately having only created a FOL file in each of the 4 directories it exports. I've ensured WLM is off line , and created empty folder on desktop. I also saw advice to remove TIFs which I have done. Tried single folder export: same result, just the FOL. Tried "repair" WLM. Didnt help.  Thoughts?