You cannot have '!'s in your user name / profile name, this breaks java horribly.

This is something we cannot control or fix

You can fix it by not having '!'s in your user name / profile name name.

(Quote from MCL-1133)
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When minecraft_server.exe or minecraft_server.jar is put into a directory with a name containing the character '!', it crashes with a java.lang.NullPointerException straight away.

This is obviouslyt not intended, and it took me quite a while to understand why my server wouldn't run.

Steps to Reproduce:
1. Make a directory called '!' (or anything containing it)
2. Put minecraft_server.exe in it.
3. Run and watch it never open.

I've tested this on both jars and exes, snapshot 13w25b and 1.5.2.