Fix greenpois0n.exe has stopped working
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Did you get “greenpois0n.exe has stopped working” alert when you are trying to jailbreak iPhone using greenpois0n on Windows 7 or Windows Vista?
How to fix “greenpois0n.exe has stopped working” error?
Right click on greenpois0n.exe, click Compatibility tab, check “Run this program in compatibility mode for” option, choose Windows XP (Service Pack 3).
Also check “Run this program as an administrator” as well, then click OK.
greenpois0n 
