Problem General GI

Hy
I am a beginner in the unit, and I have a problem with my GI General .
I have a warning.
“Directional Specular Lightmaps canno be decded on SM2.0 hardware nor when using GLES2.0”
I’ve read several article on the subject , but I 'm confused ( I do not speak English very well … ) . How to solve this problem? Thank you
my configuration :
2X GeForce GTX 980 TI
I7-5930 CPU @ 3.50 GHZ
16 GO RAM

Ignore it.

You enabled the directional specular lightmap mode in the lighting panel. Directional specular means that you will get the nicest looking lightmaps, but they are not compatible with old or lower end hardware, like mobiles - that’s what the warning is telling you. If you are targeting current generation computers and consoles, you can safely ignore the warning. If you are targeting mobile or want to support older hardware, you will need to change the lightmapping settings. This article on the documentation tells you more about the three different lightmapping modes and their performance costs.