Deploy error about Heroku

I have created a new app on Heroku on Windows XP, accessed the cr开发者_JAVA技巧eated URL, it displayed the welcome page, then I deployed Rails app data to Heroku, then accessed the same URL again, but I found it displayed an error page with an "application error". I have no idea, the Rails app is open source, I downloaded it from the internet, I have done nothing to it except overwriting the document's name.

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Run heroku logs to see what the problem is.

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did it have a database required? perhaps you need to run heroku rake db:migrate

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Try running "heroku stack" and find out what stack you are current on. I spend 5 hours before finding out that i need to create a stack on cedar to make my app works. Basically you need to run "Heroku create --stack cedar" during your first heroku create command.

Best of luck.