Flexbox Not Centering Vertically in IE

I found that ie browser have problem to vertically align inner containers, when only the min-height style is set or when height style is missing at all. What I did was to add height style with some value and that fix the issue for me.

for example :

.outer
    {
       display: -ms-flexbox;
       display: -webkit-flex;
       display: flex;

       /* Center vertically */
       align-items: center;

       /*Center horizontaly */
       justify-content: center;

       /*Center horizontaly ie */
       -ms-flex-pack: center;

        min-height: 220px; 
        height:100px;
    }

So now we have height style, but the min-height will overwrite it. That way ie is happy and we still can use min-height.

Hope this is helpful for someone.