Dead lyx

[udi]

Due to my stupidity I had to re-install Texlive 2017 on my Lubuntu 18.10 system.  Now Latex works fine (through Texworks) but Lyx does not.  I reinstalled and reconfigured lyx, but cannot compile anything.  I am sure similar panicky complaints have been seen here before-- can someone tell me what to do?  I clicked on Check latex but got back: cannot run chcktex, or some such useless response.  I can run pdflatex from the terminal and it works fine.  Somehow, Lyx has to find out about my Texdead. Thanks, Ehud Kaplan --