Problem

When embedding fonts, IE will occasionally complain that the OpenType Embedding Permissions Check failed. This typically occurs with licensed fonts, and is Microsoft's way of preventing you from using a protected font. The problem is that this sometimes occurs even when you do have the necessary license, permission, etc.

Solution

This link will take you to the homepage of a simple Command-Line program, named Embed. The link includes the instructions for running the program, though I found the instructions on this page were more useful (I included the instructions, below). The second link also gives a bit more detail about the issue and the fix. Note that  if you are using a font file conversion tool, you should run embed on your .ttf file, first, and then convert the updated file.

Compatibility

The Embed program is a 32-bit program and the executable that is available for download will not run on a 64-bit machine. However, the author was kind enough to make available the original C source-code. For your convenience, I have attached the source-code to this post, as well as a zipped folder containing both the 64 and 32-bit versions of the embed program. 

Word of Caution

The Embed program overwrites the original font file with the new one, and I do not know if this can be undone. I recommend that you backup the original before you convert. 

Program Usage:

1. Download the executable and move to the desktop with a copy of the font file.
2. Pull up a command prompt window.
3. Navigate to the desktop within the prompt
4. Execute by typing: embed.exe fontfilename.ttf
5. Viola, your font should be ready to use in IE9.