Misfired Lights

[Kingearl]

Hello all, first timer! So the previous owner wired my basement lighting. When I turn on the basement lights from the top of the stair both lights come on. But if I turn them off with the basement switch only one of the two lights go out. Any ideas what he did? Thanks in advance for the help.

 

[1Justin]

This is a UK forum, but for your purpose it probably makes little difference.
There is more than one way to correctly wire 2-way lighting, but there are numerous ways it could be wrong. One such conceivable error is as attached.
A correct way is on the left, but the closest incorrect arrangement on the right would create the effect you observe. (SL FYI is switched live to the lamp(s))-

That's not to say this is the fault..

 

[Megawatt]

Hello all, first timer! So the previous owner wired my basement lighting. When I turn on the basement lights from the top of the stair both lights come on. But if I turn them off with the basement switch only one of the two lights go out. Any ideas what he did? Thanks in advance for the help.

King it sounds to me like the travelers are crossed. The 2 wires are at the bottom of the switches which are the travelers