This article is part of the Wiki series: MSDN/TechNet Forums.
The Code Answerer medals are awarded to you when you answer questions in the TechNet or MSDN forums with code snippets in your answers. For more information about these medals (and the others), see the Profile FAQ.
There are no known current bugs with the Achievement medals for code snippets. Which means if you aren't getting these medals, then you likely need to review the requirements. You must...
1. Use the block code feature (the default feature in the Editor). You'll know when you do it correctly, because you'll see a code icon appear on the top-right corner of your post after you click Submit or Save.
2. Have your reply marked as an answer.
If you meet those two requirements, then it counts as one mark. The numbers required are high. 1 for the bronze (which you might already have), 10 for the silver (it takes much longer to meet the requirements above for 10 times than you might think), and 100 for the gold (this is actually fairly rare; not very many people have this one). You practically have to consciously try to get the medals to get the silver and gold.
For example, in this MSDN Forum thread, Peter had 6 replies marked as answer that include a code snippet in a code block. Then a few more where he missed that opportunity (pasted code that was not inserted in a code block).
However, you'll notice that none of them have the code snippet icon on the upper right corner of the posts. For example, this forum post has the code snippet icon in the upper right because of the inserted code block.
So if you have a code block but no symbol/icon, then you are likely using a custom tool or custom HTML code. Either way, those posts don't meet the requirements of #1 above.