What to do with this error: File '/tmp/lyx_tmpdir

[Wolfgang Engelmann]

What to do with this error: File '/tmp/lyx_tmpdir. I tried to rename the 
lyx file and run it again, but same error message. I renamed the 
lyx_tmpdir but it wants it back... Help appreciated, Wolfgang

Error while exporting format: LaTeX (pdflatex)File 
'/tmp/lyx_tmpdir.DOvyEMq14243/lyx_tmpbuf0/PBR-4thEdition-20170410-A.tex' 
was not closed properly