+ and - both go same direction

I have used 2.7.14 for several years now without problems.  Friday, Chromium stopped working so I reinstalled it.  Now _ and - both go the same direction.  So I reinstalled. No change.  Suggestions?  Sherline mill.

Chromium has nothing to do with no direction change.
Check wiring first, most probably loose wire inside a connector or broken wire.

I saw discussion of dirty parallel port PCI connection, so I started looking. The parallel port to controller box has a USB cord supplying power. I had taken the tower in the house where I had Ethernet because 2.7.14 has no built-in WiFi driver. I neglected to plug that cable into a USB port when I took it back to the shop. Everything works again! Thanks!

You are welcomed, always.