JAR - won't use custom MANIFEST.MF, constantly uses default

Been pullin' my hair out for hours now on this. I have programmed this project for almost 60 hours and I'm trying to JAR it all up (tried both Eclipse and command line jarring). However, I keep getting this error message when running from command line:

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I've written my own MANIFEST.MF file like this (where yourprogram.class has the main method in it)

Main-Class: package.yourprogram

I've also tried locating this manifest in a directory META-INF so that it should overwrite the default. However, when I jar it up and try to run it, I still get that message. So I made sure the MANIFEST.MF made it into the jar by using

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and sure enough, it's in there. However, when I extract the JAR and open META-INF/MANIFEST.MF in Notepad++, it doesn't show the file I created, it shows

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If I don't put the MANIFEST.MF file into META-INF, then there are 2 MANIFEST.MF files (one in the default directory and one in META-INF). In this case, the one in the default directory IS the one I created, but the one in META-INF is that default one and I STILL get that error message.

This all happens when I try it in both command line AND eclipse. How do I stop this default MANIFEST.MF file from being used? How do I stop it from overwriting mine when I use META-INF/MANIFEST.MF? Why haven't I had this problem before? Bah!!

Thanks in advance