For this tutorial, I will use this rap file as an example:
Code:
17 5D DC D7 E2 0F 3B FB B7 1E E8 2D 0E FC 27 A3
EP0001-BLES01138_00-MPDLC00000000001.rap
*Note: Sometimes the hex codes have spaces between them, such as the one above. Others times they don't have spaces between them and look like 175DDCD7E20F3BFBB71EE82D0EFC27A3. It doesn't matter.


1. First download and install HxD (a free hex editor). Just search HxD in the search engine of your choice. You can get a portable version of HxD if you prefer as well.

2. Open HxD and make a new file
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3. Copy and paste the hex code into the new file you just made. In this case, it would be 17 5D DC D7 E2 0F 3B FB B7 1E E8 2D 0E FC 27 A3
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*Note: Just click OK when it asks "This operation changes the file-size. Do you want to continue?"

4. Save the file with the correct filename. In this case, it would be EP0001-BLES01138_00-MPDLC00000000001.rap
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To check if you did it right. The size of the rap file you just saved should be 16 bytes.