Why didn't embed font style work on IE? How to fix

Why didn't embed font style work on IE? How to fix this isues?

Embed font not work with IE

@font-face {
font-family: MyCustomFont;
src: url("Aspire-DemiBold.ttf") /* TTF file for CSS3 browsers */
}

Embed font worked with IE

@font-face {
font-family: MyCustomFont;
src: url("Aspire-DemiBold.eot") /* EOT file for IE */
}
@font-face {
font-family: MyCustomFont;
src: url("Aspire-DemiBold.ttf") /* TTF file for CSS3 browsers */
}

How to create a font with format .eot:

This it tool to convert font format from .ttf to .eot: Concert .ttf to .eot!

Please comment if you have any solution for this issues.