That eboot seems to be half of a 1.50 Kernel eboot.
Move the folder you have it in to GAME150, and if you have any 1.50 apps there make a copy of the folder with the '%', and rename it to whatever you have the folder with dosbox named. Just add a '%' at the end. (e.g, DosBox and DosBox%)
If you have a slim or do not have 1.50 kernel installed, then it won't work.
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